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1
Chong, Harold Meng Hoon. "Photonic crystal and photonic wire structures for photonic integrated circuits." Thesis, University of Glasgow, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407719.
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Zhu, Rui. "Integrated nano-optomechanics in photonic crystal." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS258/document.
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Les oscillateurs de référence de haute pureté sont actuellement utilisés dans un grand nombre d’applications allant du contrôle de fréquence aux horloges pour les radars, les GPS et l’espace... Les tendances actuelles dans ce domaine requièrent des architectures miniaturisées avec la génération de signaux directement dans la gamme de fréquences d’intérêt, autour de quelques GHz. Récemment, de nouvelles architectures basées sur les principes de l’optomécanique ont vu le jour dans ce but. De tels oscillateurs optomécanique génèrent non seulement des signaux hyperfréquences directement dans la gamme de fréquences GHz avec éventuellement un faible bruit de phase, mais permettent également un degré élevé d'intégration sur puce. Ce travail de thèse s'inscrit dans cette démarche. L’oscillateur optomécanique étudié se compose de cavités à cristaux photoniques suspendues couplées à des guides d’ondes silicium sur isolant intégrés dans une architecture tridimensionnelle. Ces cavités abritent des modes optiques fortement confinés autour de 1550nm et des modes mécaniques dans le GHz. De plus, ces structures présentent un recouvrement spatial entre phonon et photon élevé. Il en résulte un couplage optomécanique amélioré. Cette force de couplage optomécanique améliorée est ici sondée optiquement sur des structures à cristaux photoniques de conception optimisée. Ces cavités sont réalisées dans des matériaux semi-conducteurs III-V dont la piézoélectricité nous permet d'intégrer des outils supplémentaires pour sonder et contrôler les vibrations mécaniques via un pilotage capacitif, piézoélectrique ou acoustique. Ce contrôle total des modes mécaniques et de l’interaction optomécanique ouvre la voie à la mise en œuvre de circuits intégrés pour le verrouillage par injection et des boucles de rétroaction permettant de réduire le bruit de phase de l’oscillateurHigh purity reference oscillators are currently used in a wide variety of frequency control and timing applications including radar, GPS, space... Current trends in such fields call for miniaturized architectures with direct signal generation in the frequency range of interest, around few GHz. Recently, novel optomechanically-enhanced architectures have emerged with this purpose. Such optomechanically-driven oscillators not only generate microwave signals directly in the GHz frequency range with possibly low phase noise but also are amenable to a high degree of integration on single chip settings. This PhD work falls within this scope. The optomechanically-driven oscillator under study consists of suspended photonic crystal cavities coupled to integrated silicon-on-insulator waveguides in a three-dimensional architecture. These cavities harbor highly-confined optical modes around 1,55 µm and mechanical modes in the GHz and most importantly, feature a high phonon-photon spatial overlap, all resulting in an enhanced optomechanical coupling. This enhanced optomechanical coupling strength is here probed optically on photonic crystal structures with optimized design. These cavities are hosted in III-V semiconductor materials whose piezoelectricity enable us to integrate additional tools for probing and controlling mechanical vibrations via capacitive, piezoelectric or acoustic driving. This full control over the mechanical modes and optomechanical interaction, paves the way towards the implementation of integrated injection locking circuits of feedback loops for reducing the phase noise of the oscillator
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Mekis, Attila 1972. "Theoretical design of photonic crystal devices for integrated optical circuits." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9125.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Physics, 2000.Includes bibliographical references (p. 139-143).
In this thesis we investigate novel photonic crystal devices that can be used as building blocks of all-optical circuits. We contrast the behavior of light in photonic crystal systems and in their traditional counterparts. We exhibit that bends in photonic crystals are able to transmit light with over 90% efficiency for large bandwidths and with 100% efficiency for specific frequencies. In contrast to traditional waveguides, bound states in photonic crystal waveguides can also exist in constrictions and above the cutoff frequency. We discuss how to lower reflections encountered when photonic crystal waveguides are terminated, both in an experimental setup as well as in numerical simulations. We show that light can be very efficiently coupled into and out of photonic crystal waveguides using tapered dielectric waveguides. In time-domain simulations of photonic crystal waveguides, spurious reflections from cell edges can be eliminated by terminating the waveguide with a Bragg reflector waveguide. We demonstrate novel lasing action in two-dimensional photonic crystal slabs with gain media, where lasing occurs at saddle points in the band structure, in contrast to one-dimensional photonic crystals. We also design a photonic crystal slab with organic gain media that has a TE-like pseudogap. We demonstrate that such a slab can support a high-Q defect mode, enabling low threshold lasing, and we discuss how the quality factor depends on the design parameters. We also propose to use two dimensional photonic crystal slabs as directionally efficient free-space couplers. We draft methods to calculate the coupling constant both numerically and analytically, using a finite-difference time-domain method and the volume current method with a Green's function approach, respectively.
by Attila Mekis.
Ph.D.
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Schillinger, Matthias. "Maximally localized photonic Wannier functions for the highly efficient description of integrated Photonic Crystal circuits." [S.l. : s.n.], 2006. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007183.
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Lin, Chunchen. "Semiconductor-based nanophotonic and terahertz devices for integrated circuits applications." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 7.48 Mb., 180 p, 2006. http://wwwlib.umi.com/dissertations/fullcit/3221130.
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Reinke, Charles M. "Design, simulation, and characterization toolset for nano-scale photonic crystal devices." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/33932.
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The objective of this research is to present a set of powerful simulation, design,
and characterization tools suitable for studying novel nanophotonic devices. The
simulation tools include a three-dimensional finite-difference time-domain code adapted
for parallel computing that allows for a wide range of simulation conditions and material
properties to be studied, as well as a semi-analytical Green's function-based complex
mode technique for studying loss in photonic crystal waveguides. The design tools
consist of multifunctional photonic crystal-based template that has been simulated with
nonlinear effects and measured experimentally, and planar slab waveguide structure that
provides highly efficient second harmonic generation is a chip-scale device suitable for
photonic integrated circuit applications. The characterization tool is composed of a
phase-sensitive measurement system using a lock-in amplifier and high-precision optical
stages, suitable for probing the optical characteristics of nanoscale devices. The high
signal-to-noise ratio and phase shift data provided by the lock-in amplifier allow for
accurate transmission measurements as well as a phase spectrum that contains
information about the propagation behavior of the device beyond what is provided by the
amplitude spectrum alone.
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Mulot, Mikaël. "Two-Dimensional Photonic Crystals in InP-based Materials." Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3751.
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Photonic crystals (PhCs) are structures periodic in thedielectric constant. They exhibit a photonic bandgap, i.e., arange of wavelengths for which light propagation is forbidden.Engineering of defects in the PhC lattice offers new ways toconfine and guide light. PhCs have been manufactured usingsemiconductors and other material technologies. This thesisfocuses on two-dimensional PhCs etched in InP-based materials.Only recently, such structures were identified as promisingcandidates for the realization of novel and advanced functionsfor optical communication applications.
The primary focus was on fabrication and characterization ofPhC structures in the InP/GaInAsP/InP material system. Thedemands on fabrication are very high: holes as small as100-300nm in diameter have to be etched at least as deep as 2µm. Thus, different etch processes had to be explored andspecifically developed for InP. We have implemented an etchingprocess based on Ar/Cl2chemically assisted ion beam etching (CAIBE), thatrepresents the state of the art PhC etching in InP.
Different building blocks were manufactured using thisprocess. A transmission loss of 10dB/mm for a PhC waveguide, areflection of 96.5% for a 4-row mirror and a record qualityfactor of 310 for a 1D cavity were achieved for this materialsystem. With an etch depth of 4.5 µm, optical loss wasfound to be close to the intrinsic limit. PhC-based opticalfilters were demonstrated using (a) a Fabry-Pérot cavityinserted in a PhC waveguide and (b) a contra-directionalcoupler. Lag effect in CAIBE was utilized positively to realizehigh quality PhC taper sections. Using a PhC taper, a couplingefficiency of 70% was demonstrated from a standard ridgewaveguide to a single line defect PhC waveguide.
During the course of this work, InP membrane technology wasdeveloped and a Fabry-Pérot cavity with a quality factorof 3200 was demonstrated.
Keywords:photonic crystals, photonic bandgap materials,indium phosphide, dry etching, chemically assisted ion beametching, reactive ion etching, electron beam lithography,photonic integrated circuits, optical waveguides, resonantcavities, optical filtering, finite difference time domain,plane wave expansion.
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Nagy, Jonathan Tyler. "Periodic Poling of Lithium Niobate Thin Films for Integrated Nonlinear Optics." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587673156665861.
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Lou, Fei. "Design, fabrication and characterization of plasmonic components based on silicon nanowire platform." Doctoral thesis, KTH, Optik och Fotonik, OFO, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143953.
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Optical interconnects based on CMOS compatible photonic integrated circuits are regarded as a promising technique to tackle the issues traditional electronics faces, such as limited bandwidth, latency, vast energy consumption and so on. In recent years, plasmonic integrated components have gained great attentions due to the properties of nano-scale confinement, which may potentially bridge the size mismatch between photonic and electronic circuits. Based on silicon nanowire platform, this thesis work studies the design, fabrication and characterization of several integrated plasmonic components, aiming to combine the benefits of Si and plasmonics. The basic theories of surface plasmon polaritons are introduced in the beginning, where we explain the physics behind the diffraction-free confinement. Numerical methods frequently used in the thesis including finite-difference time-domain method and finite-element method are then reviewed. We summarize the device fabrication techniques such as film depositions, e-beam lithography and inductively coupled plasma etching as well as characterization methods, such as direct measurement method, butt coupling, grating coupling etc. Fabrication results of an optically tunable silicon-on-insulator microdisk and III-V cavities in applications as light sources for future nanophotonics interconnects are briefly discussed. Afterwards we present in details the experimental demonstrations and novel design of plasmonic components. Hybrid plasmonic waveguides and directional couplers with various splitting ratios are firstly experimentally demonstrated. The coupling length of two 170 nm wide waveguides with a separation of 140 nm is only 1.55 µm. Secondly, an ultracompact polarization beam splitter with a footprint of 2×5.1 μm2 is proposed. The device features an extinction ratio of 12 dB and an insertion loss below 1.5 dB in the entire C-band. Thirdly, we show that plasmonics offer decreased bending losses and enhanced Purcell factor for submicron bends. Novel hybrid plasmonic disk, ring and donut resonators with radii of ~ 0.5 μm and 1 μm are experimentally demonstrated for the first time. The Q-factor of disks with 0.5 μm radii are , corresponding to Purcell factors of . Thermal tuning is also presented. Fourthly, we propose a design of electro-optic polymer modulator based on plasmonic microring. The figure of merit characterizing modulation efficiency is 6 times better comparing with corresponding silicon slot polymer modulator. The device exhibits an insertion loss below 1 dB and a power consumption of 5 fJ/bit at 100 GHz. At last, we propose a tightly-confined waveguide and show that the radius of disk resonators based on the proposed waveguide can be shrunk below 60 nm, which may be used to pursue a strong light-matter interaction. The presented here novel components confirm that hybrid plasmonic structures can play an important role in future inter- and intra-core computer communication systems.QC 20140404
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Neto, Hugo Daniel Barbosa. "Packaging of photonic integrated circuits." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23552.
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Mestrado em Engenharia Eletrónica e TelecomunicaçõesWith the continuous evolution of optical communication systems, emerged a need for high-performance optoelectronic elements at lower costs. Photonic packaging plays a key role for the next-generation of optical devices. In this work a standard packaging design rules is described, covering both the electrical and optical-packaging exploring both active and passive adjusting techniques, as well as the thermal management of the photonic integrated circuit (PIC). First a process for fiber-to-chip coupling with custom made ball-lensed fibers, is performed and tested initially in a testing-chip and thereafter in a manufactured practical study-case composed by a silicon holder with an InP distributed feedback (DFB) laser. The process of manufacturing etched V-grooves for fiber alignment is approached in detail. After this, for electrical interconnects and radio frequency (RF) packaging, both wire-bonding and flip-chip technique are discussed, and a characterization of the s-parameters in a PIC with wire-bonding is presented. A technique based on ruthenium-based sensors and platinum and titanium-based sensors for thermal control of the PIC is studied and the tested using a custom made PCB designed exclusively for that purpose.
Com a constante evolução dos sistemas de comunicação óticos veio a necessidade de componentes optoelectrónicos de elevada performance a custos relativamente baixos. O encapsulamento ótico tem um papel chave nos dispositivos óticos de última geração. Neste trabalho são descritas as regras de um processo de encapsulamento padrão, que abrange tanto o encapsulamento elétrico e ótico onde são exploradas técnicas de ajustamento ativas e passivas bem como o controlo térmico do circuito ótico integrado (PIC). No início foi efetuado um processo de acoplamento da fibra ao chip com fibras de lente esférica personalizadas, numa primeira usando um chip de teste e de seguida num caso de estudo prático que consiste numa estrutura composta por um holder de silício com um laser de realimentação distribuída (DFB). É abordado em detalhe o processo de fabricação de V-grooves para o alinhamento da fibra com o chip. De seguida são apresentadas e discutidas as técnicas de wire-bonding e flip-chip para o encapsulamento elétrico e ligação dos conectores de radiofrequência (RF), é feito um estudo onde são apresentados os resultados da caraterização dos parâmetros S de um PIC com wire-bonding. Para o controlo térmico do módulo é apresentada uma técnica baseada em sensores de temperatura de ruténio e sensores de Platina e titânio testada numa PCB personalizada
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Yang, Gang. "Compact Photonic Integrated Passive Circuits." Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/26958.
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Photonic Integrated Circuits (PICs) based on silicon photonics have received great interest due to the low loss caused by the high-refractive-index contrast and the complementary metal-oxide semiconductor compatibility. The need for high-density, high-yield, low-cost, low-power consumption, and large-scale on-chip photonic integration requires the technologies to further minimize the size while exhibiting high performance. Moreover, the fast development and expansion of silicon photonics devices for different applications and functionalities require effective design approaches to optimize the device performance while reducing the design complexity.
In this thesis, several fundamental components for PICs are presented as the building blocks for advanced photonic circuits. To test the effectiveness of the design, Mach–Zehnder interferometers are simulated and fabricated on a Silicon-on-Insulator (SOI) platform, which shows a good agreement between the experimental and simulation results. Moreover, compact vertical grating couplers with broad optical bandwidth are studied. Experimental results show the compact size and the light coupling capabilities.
Multimode Interference (MMI) splitter acts as one critical component in PICs. However, the minimum requirement of mid-to-mid channel spacing to avoid crosstalk limits the MMI size to be further reduced and thus limits the component density in the photonic integration. To solve this problem, a compact SOI MMI power splitter based on optical strip barriers is presented to achieve high crosstalk reduction. Three different MMI power splitters are designed and simulated with an ultra-small device footprint, high uniformity, while maintaining a low insertion loss of 0.4dB.
Inverse design methods with different optimization algorithms are utilized to design compact and high-performance PIC components. Firstly, a sequential least-squares programming algorithm is introduced to inverse design a waveguide crossing. This gradient-based algorithm is suitable for simple structures with fewer parameters, or a good starting point can be obtained from experience or physical theories.
Secondly, a novel dynamic iterative batch optimization method is presented in the thesis to design a high-performance segmented mode expander. In the simulation, the optimized structure achieves a coupling efficiency of 81% for TE polarization at the wavelength of 1550nm. It also shows a simulated transmission loss of lower than -1.137dB within 60nm bandwidth. This approach paves the way for the rapid design of PIC components with a compact footprint. Additionally, a Direct Binary Search (DBS) algorithm is introduced for designing pixel-like structures with binary-value-represented topology patterns, where a 3dB beam splitter is used in the design. DBS algorithm can be utilized to generate a high-quality dataset used for deep learning acceleration methods.
To solve the time-efficiency and non-scalable issues of conventional inverse design methods, a neural network-based inverse design approach is presented and applied on the design of a wavelength demultiplexer structure. The method solves the data domain shift problem that existed in the conventional tandem network architecture and improves the prediction accuracy with a 99% validation accuracy. It also shows high stability and robustness to the quantity and quality of training data. The demonstrated wavelength demultiplexer has an ultra-compact footprint of 2.6×2.6μm2, a high transmission efficiency with a transmission loss of -2dB, and a low crosstalk around -7dB simultaneously.
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Tai, Chao-Yi. "Tantalum pentoxide waveguides for photonic crystal circuits." Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409900.
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Marinins, Aleksandrs. "Polymer Components for Photonic Integrated Circuits." Doctoral thesis, KTH, Skolan för teknikvetenskap (SCI), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-219556.
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Optical polymers are a subject of research and industry implementation for many decades. Optical polymers are inexpensive, easy to process and flexible enough to meet a broad range of application-specific requirements. These advantages allow a development of cost-efficient polymer photonic integrated circuits for on-chip optical communications. However, low refractive index contrast between core and cladding limits light confinement in a core and, consequently, integrated polymer device miniaturization. Also, polymers lack active functionality like light emission, amplification, modulation, etc. In this work, we improved a performance of integrated polymer waveguides and demonstrated active waveguide devices. Also, we present novel Si QD/polymer optical materials. In the integrated device part, we demonstrate optical waveguides with enhanced performance. Decreased radiation losses in air-suspended curved waveguides allow low-loss bending with radii of only 15 µm, which is far better than >100 µm for typical polymer waveguides. Another study shows a positive effect of thermal treatment on acrylate waveguides. By heating higher than polymer glass transition temperature, surface roughness is reflown, minimizing scattering losses. This treatment method enhances microring resonator Q factor more than 2 times. We also fabricated and evaluated all-optical intensity modulator based on PMMA waveguides doped with Si QDs. We developed novel hybrid optical materials. Si QDs are encapsulated into PMMA and OSTE polymers. Obtained materials show stable photoluminescence with high quantum yield. We achieved the highest up to date ~65% QY for solid-state Si QD composites. Demonstrated materials are a step towards Si light sources and active devices. Integrated devices and materials presented in this work enhance the performance and expand functionality of polymer PICs. The components described here can also serve as building blocks for on-chip sensing applications, microfluidics, etc.QC 20171207
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Alipour, Motaallem Seyed Payam. "Reconfigurable integrated photonic circuits on silicon." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51792.
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Integrated optics as a platform for signal processing offers significant benefits such as large bandwidth, low loss, and a potentially high degree of reconfigurability. Silicon (Si) has unique advantages as a material platform for integration, as well as properties such as a strong thermo-optic mechanism that allows for the realization of highly reconfigurable photonic systems. Chapter 1 is devoted to the discussion of these advantages, and Chapter 2 provides the theoretical background for the analysis of integrated Si-photonic devices. The thermo-optic property of Si, while proving extremely useful in facilitating reconfiguration, can turn into a nuisance when there is a need for thermally stable devices on the photonic chip. Chapter 3 presents a technique for resolving this issue without relying on a dynamic temperature stabilization process. Temperature-insensitive (or “athermal”) Si microdisk resonators with low optical loss are realized by using a polymer overlayer whose thermo-optic property is opposite to that of Si, and TiO2 is introduced as an alternative to polymer to deal with potential CMOS-compatibility issues. Chapter 4 demonstrates an ultra-compact, low-loss, fully reconfigurable, and high-finesse integrated photonic filter implemented on a Si chip, which can be used for RF-photonic as well as purely optical signal processing purposes. A novel, thermally reconfigurable reflection suppressor is presented in Chapter 5 for on-chip feedback elimination which can be critical for mitigating spurious interferences and protecting lasers from disturbance. Chapter 6 demonstrates a novel device for on-chip control of optical fiber polarization. Chapter 7 deals with select issues in the implementation of Si integrated photonic circuits. Chapter 8 concludes the dissertation.
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Rodrigues, Carla Iolanda Costa. "Photonic integrated circuits for NG-EPON." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22732.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesAlong with privacy and security, the growth of demand from the consumer for higher bandwidth presents one of the most important modern challenges in telecommunications infrastructures. The researchers were encouraged to nd not only e cient but also the economically viable solutions capable of meeting the growing needs of the consumer. Optical communications are the way that can accompany this growth. The Passive Optical Network (PON) is an architecture that shares the ber bandwidth among several users. There has been a constant study under this topic for the purpose of using all the ber abilities and to nd new solutions to keep the access network simple. Photonic Integrated Circuits (PICs) are a technology that emerged to help the complexity of the hardware that exists nowadays. It is a single chip capable of integrating numerous optical components, which leads to a reduced complexity, size and power consumption. These are the important characteristics that make the PICs a powerful tool to use in several applications. This dissertation presents a monolithic PIC transceiver in the context of Next Generation of Ethernet Passive Optical Network (NG-EPON) which aims to design and implement integrated optical circuits for future access networks. The transceiver architecture is able to be used as an Optical Network Unit (ONU) with a 4 channels approach for 100 Gb/s solutions. The present work contributed for the FUTPON project supported by P2020.
Em par com a privacidade e segurança, a crescente procura do consumidor por maiores larguras de banda apresenta um dos mais importantes desafios modernos das infraestruturas de telecomunicações. Esta procura incentiva assim a investigação de novas soluções não são eficientes, mas também economicamente viáveis, capazes de satisfazer as crescentes necessidades do consumidor. As comunicações óticas apresentam ser o meio apropriado para acompanhar este crescimento. A Rede Óptica Passiva (PON) e uma arquitectura usada para distribuição de fibra ótica ate ao consumidor final. Esta tecnologia permite dividir a largura de banda de uma única fibra por diferentes clientes. Tem havido um estudo constante no âmbito deste tópico para conseguir tirar máximo partido das capacidades da fibra e de modo a encontrar novas soluções para tornar este método mais simples. Os Circuitos Oticos Integrados (PIC) sao uma tecnologia que surge para ajudar na complexidade do hardware existente hoje em dia. Consiste num único chip capaz de integrar vários componentes óticos, o que leva a uma diminuição da complexidade, tamanho e redução do consumo de energia. Estas características fazem com que seja uma tecnologia vantajosa para uso em diferentes aplicações. O desenho e a implementação da arquitectura do transrecetor em formato PIC no contexto da Next Generation of Ethernet Passive Optical Network (NG-EPON), e o principal objectivo desta dissertação onde visa o desenvolvimento circuitos óticos integrados para redes oticas de acesso futuras. Esta arquitectura devera ser utilizada como Optical Network Unit (ONU) contendo 4 canais para atingir 100 Gb/s. Este trabalho contribuiu para o projecto FUTPON suportado pelo P2020.
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Liu, Weilin. "Ultra-Fast Photonic Signal Processors Based on Photonic Integrated Circuits." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36446.
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Photonic signal processing has been considered a promising solution to overcome the inherent bandwidth limitations of its electronic counterparts. Over the last few years, an impressive range of photonic integrated signal processors have been proposed with the technological advances of III-V and silicon photonics, but the signal processors offer limited tunability or reconfigurability, a feature highly needed for the implementation of programmable photonic signal processors.
In this thesis, tunable and reconfigurable photonic signal processors are studied. Specifically, a photonic signal processor based on the III-V material system having a single ring resonator structure for temporal integration and Hilbert transformation with a tunable fractional order and tunable operation wavelength is proposed and experimentally demonstrated. The temporal integrator has an integration time of 6331 ps, which is an order of magnitude longer than that provided by the previously reported photonic integrators. The processor can also provide a continuously tunable fractional order and a tunable operation wavelength.
To enable general-purpose signal processing, a reconfigurable photonic signal processor based on the III-V material system having a three-coupled ring resonator structure is proposed and experimentally demonstrated. The reconfigurability of the processor is achieved by forward or reverse biasing the semiconductor optical amplifiers (SOAs) in the ring resonators, to change the optical geometry of the processor which allows the processor to perform different photonic signal processing functions including temporal integration, temporal differentiation, and Hilbert transformation. The integration time of the signal processor is measured to be 10.9 ns, which is largely improved compared with the single ring resonator structure due to a higher Q-factor. In addition, 1st, 2nd, and 3rd of temporal integration operations are demonstrated, as well as a continuously tunable order for differentiation and Hilbert transformation. The tuning range of the operation wavelength is 0.22 nm for the processor to perform the three functions.
Compared with the III-V material system, the CMOS compatible SOI material system is more cost effective, and it offers a smaller footprint due to the strong refractive index contrast between silicon and silica. Active components such as phase modulators (PMs) can also be implemented. In this thesis, two photonic temporal differentiators having an interferometer structure to achieve active and passive fractional order tuning are proposed and experimentally demonstrated. For both the active and passive temporal differentiators, the fractional order can be tuned from 0 to 1. For the active temporal differentiator, the tuning range of the operation wavelength is 0.74 nm. The use of the actively tunable temporal differentiator to perform high speed coding with a data rate of 16 Gbps is also experimentally demonstrated.
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Williams, Ryan Daniel. "Photonic integrated circuits for optical logic applications." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42025.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references.
The optical logic unit cell is the photonic analog to transistor-transistor logic in electronic devices. Active devices such as InP-based semiconductor optical amplifiers (SOA) emitting at 1550 nm are vertically integrated with passive waveguides using the asymmetric twin waveguide technique and the SOAs are placed in a Mach-Zehnder interferometer (MZI) configuration. By sending in high-intensity pulses, the gain characteristics, phase-shifting, and refractive indices of the SOA can be altered, creating constructive or deconstructive interference at the MZI output. Boolean logic and wavelength conversion can be achieved using this technique, building blocks for optical switching and signal regeneration. The fabrication of these devices is complex and the fabrication of two generations of devices is described in this thesis, including optimization of the mask design, photolithography, etching, and backside processing techniques. Testing and characterization of the active and passive components is also reported, confirming gain and emission at 1550 nm for the SOAs, as well as verifying evanescent coupling between the active and passive waveguides. In addition to the vertical integration of photonic waveguides, Esaki tunnel junctions are investigated for vertical electronic integration. Quantum dot formation and growth via molecular beam epitaxy is investigated for emission at the technologically important wavelength of 1310 nm. The effect of indium incorporation on tunnel junctions is investigated. The tunnel junctions are used to epitaxially link multiple quantum dot active regions in series and lasers are designed, fabricated, and tested.
by Ryan Daniel Williams.
Ph.D.
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Franco, Eduardo Vala. "Photonic integrated circuits for next generation PONs." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23473.
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Mestrado em Engenharia Eletrónica e TelecomunicaçãoWe are living in a time where communications became essential for most of our lives, whether it's in the business world, or in our own homes. The increasing need of higher bandwidth inhibits other networks other than optical ber based ones. Nowadays communications are responsible for a substantial percentage of our energetic footprint, hence Passive Optical Network(PON) are a strong contender for the next step of network implementation. These networks present a low energy consumption because between the transmitter and the receiver the signal stays in the optical domain. Although the increasing needs of bandwidth is almost across the communication world, certain services/identities need more bandwidth whether is download or upload. It's easy to understand that di erent consumers have unique needs. It's necessary to develop an architecture that serves all the costumers, in other words, there is a need for a network that provides high bitrate tra c to the users that needs it but also a network that serves the low end user that is not interested in this increase of bandwidth and therefore price in ation. There is today technologies yet to be widely implemented like NG-PON2 that were not implemented in a large scale because they dont represent a nancial return to the telecom operators simply because there is not enough user that requires the high bandwidth delivered by NG-PON2. It's necessary to nd a solution that includes not only the modern technologies but also the already implemented ones. With the objective of nding a solution for the problems mentioned before, this dissertation has the objective of designing a Photonic Integrated Circuit(PIC) that aims to be a transceiver of a Multitech Network that will be composed by the following technologies: Video-Overlay, XG-PON e NG-PON2. This dissertation presents an approach on Passive Optical Networks( PON) and the standards of the said technologies as well as a study of the components needed to assemble the transceiver using the programs ASPIC and VPI Photonics . In the end, there will be presented an architecture for the transceiver to be used in a Optical Network Unit(ONU), and the respective mask Layout.
Vivemos numa época em que as comunicações se tornaram essenciais para grande parte da nossa vida, seja no mundo empresarial, seja nas nossas habitações. A crescente necessidade de aumento de largura de banda inviabiliza outras redes que não baseadas em braotica. Actualmente as comunicações são responsáveis por uma percentagem substancial dos nossos gastos energéticos, justamente por este facto Passive Optical Networks(PON) sao as principais candidatas ao próximo passo no desenvolvimento de redes. Estas apresentam menor consumo energético, pois entre o emissor e o receptor todo o sinal permanece no domínio óptico. Apesar da necessidade de largura de banda estar a aumentar de um modo transversal no mundo das telecomunicações, certos serviços/entidades necessitam de maiores velocidades tanto em termos de download como em termos de upload. E então fácil de perceber que consumidores diferentes têm necessidades diferentes. E necessário encontrar uma arquitectura que agrade a quem necessita de maiores larguras de banda mas também a quem não necessita de um aumento significativo e que, não está disposto a pagar por este. Existem neste momento tecnologias que ainda não foram implementadas em grandes escalas, como o caso de Next Generation Passive Optical Network (NG-PON2), porque não simbolizam um retorno financeiro para as grande operadores, uma vez que o número de potenciais consumidores de tais velocidades ainda não e substancialmente grande. E necessário encontrar uma solução que não so englobe as novas tecnologias como também as já existentes. Com o objectivo de se encontrar um solução para os problemas acima referidos, este trabalho assenta na elaboração de um Circuito integrado fotonico que visa ser um transrecetor de uma arquitetura multi-tecnologia em que irão ser incorporadas tecnologias como Video-Overlay, 10 Gigabit-capable Passive Optical Network (XG-PON) e NG-PON2. Esta dissertação apresenta uma abordagem as Redes Oticas Passivas e também um estudo feito aos componentes usados no transreceptor usando os programas Aspic e VPI Photonics . Porém ser a apresentado o desenho final do transreceptor que ser a usado numa Optical Network Unit(ONU).
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Mahendra, Andri. "Electronic Photonic Integrated Circuits and Control Systems." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17806.
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Photonic systems can operate at frequencies several orders of magnitude higher than electronics, whereas electronics offers extremely high density and easily built memories. Integrated photonic-electronic systems promise to combine advantage of both, leading to advantages in accuracy, reconfigurability and energy efficiency. This work concerns of hybrid and monolithic electronic-photonic system design. First, a high resolution voltage supply to control the thermooptic photonic chip for time-bin entanglement is described, in which the electronics system controller can be scaled with more number of power channels and the ability to daisy-chain the devices. Second, a system identification technique embedded with feedback control for wavelength stabilization and control model in silicon nitride photonic integrated circuits is proposed. Using the system, the wavelength in thermooptic device can be stabilized in dynamic environment. Third, the generation of more deterministic photon sources with temporal multiplexing established using field programmable gate arrays (FPGAs) as controller photonic device is demonstrated for the first time. The result shows an enhancement to the single photon output probability without introducing additional multi-photon noise. Fourth, multiple-input and multiple-output (MIMO) control of a silicon nitride thermooptic photonic circuits incorporating Mach Zehnder interferometers (MZIs) is demonstrated for the first time using a dual proportional integral reference tracking technique. The system exhibits improved performance in term of control accuracy by reducing wavelength peak drift due to internal and external disturbances. Finally, a monolithically integrated complementary metal oxide semiconductor (CMOS) nanophotonic segmented transmitter is characterized. With segmented design, the monolithic Mach Zehnder modulator (MZM) shows a low link sensitivity and low insertion loss with driver flexibility.
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Sun, Xiaolan. "Quantum Well Intermixing For Photonic Integrated Circuits." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194900.
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In this thesis, several aspects of GaAsSb/AlSb multiple quantum well (MQW) heterostructures have been studied. First, it was shown that the GaAsSb MQWs with a direct band gap near 1.5 μm at room temperature could be monolithically integrated with AlGaSb/AlSb or AlGaAsSb/AlAsSb Bragg mirrors, which can be applied to Vertical Cavity Surface Emitting Lasers (VCSELs). Secondly, an enhanced photoluminescence from GaAsSb MQWs was reported. The photoluminescence strength increased dramatically with arsenic fraction as conjectured. The peak photoluminescence from GaAs(0.31)Sb(0.69) was 208 times larger than that from GaSb. Thirdly, the strong photoluminescence from GaAsSb MQWs and the direct nature of the band gap near 1.5 μm at room temperature make the material favorable for intermixing studies. The samples were treated with ion implantation followed by rapid thermal annealing (RTA). A band gap blueshift as large as 198 nm was achieved with a modest ion dose and moderate annealing temperature. Photoluminescence strength for implanted samples generally increased with the annealing temperature. The energy blueshift was attributed to the interdiffusion of both the group III and group V sublattices. Finally, based on the interesting properties of GaAsSb MQWs, including the direct band gap near 1.5 μm, strong photoluminescence, a wide range of wavelength (1300 – 1500 nm) due to ion implantation-induced quantum well intermixing (QWI), and subpicosecond spin relaxation reported by Hall et al, we proposed to explore the possibilities for ultra-fast optical switching by investigating spin dynamics in semiconductor optical amplifiers (SOAs) containing InGaAs and GaSb MQWs. For circularly polarized pump and probe waves, the numerical simulation on the modal indices showed that the difference between the effective refractive index of the TE and TM modes was quite large, on the order of 0.03, resulting in a significant phase mismatch in a traveling length larger than 28 μm. Thus the FWM conversion efficiency was exceedingly small and the FWM mechanism in SOAs used for investigation of all-optical polarization switching was strongly limited.
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Möller, Anton. "Piezoelectric tuning of integrated photonic delay circuits." Thesis, KTH, Tillämpad fysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260415.
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Cantarella, Giuseppe. "Design, microfabrication and characterisation of Photonic Integrated Circuits." Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=28500.
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This doctoral dissertation deals with the design, fabrication and characterization of state-of-the-art Photonic Integrated Circuits (PICs) for non-linear applications. Silicon PICs is a technology mainly used for application in telecommunications and quantum optics. The strong third order non-linearity of silicon makes it also attractive for non-linear PIC design. In FWM applications, SOI technology can be used not only for non-linear generation but also to fabricate photonic filters to remove the residual pump. This thesis deals with three requirements for the realisation of on-chip FWM optical devices, the dual polarisation rejection of the pump on-chip and the integration and stabilisation of the FWM source and optical filter. In this work two of the most used SOI photonic integrated filters, ring resonators and Bragg gratings, are presented. These devices present two different solutions for high extinction(≈ 60 dB) dual polarisation filtering. An integrated structure of non-linear source and filter is presented. The device used for non-linear generation is then monolithically integrated with a novel ring resonators cascade filter technology. FWM experiments were carried out obtaining an on chip pump high dual polarisation extinction of 62 dB with a low insertion loss for the propagating signal and idler of only 1.8 dB.The realisation of a microprocessor feedback loop stabilisation system integrated with SOI non-linear structures is also demonstrated. The system is based on a local thermal heater element on-chip used to stabilise the PICs against thermal refractive index variations. Using this method, a silicon π-phase shifted grating with a cavity Q-factor of 40k is demonstrated to operate over an ambient temperature detuning range of 40 oC and injection wavelength range of 1.5 nm, nearly 3 orders of magnitude greater than the resonant cavity line width. The last part of this work is dedicated to the description of a custom made laser photolitography system for rapid prototyping of PIC designs, a tool designed to overcome the costs of the typical lithography systems and drastically decrease the time required for multiple micro-fabrications. The hardware and the software created for this tool are presented together with the first results on the fabrication of SU-8 Photoresist (SU − 8) on Silicon Dioxide (SiO2) waveguides, bends, Mach Zehnder interferometers and ring resonators.
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KAPLAN, ALI EMRE. "APPLICATIONS OF COUPLED RESONATORS IN PHOTONIC INTEGRATED CIRCUITS." Doctoral thesis, Università degli studi di Ferrara, 2020. http://hdl.handle.net/11392/2487877.
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Progress in photonic integrated circuits (PICs) enables contemporary solutions that cover more and more technology areas, including optical networking, computing systems and sensing. The capabilities of PICs continuously enrich thanks to the introduction of new photonic circuit elements. Among them, Micro Ring Resonators (MMRs) receive particular interest because of their wide range of functional properties that can serve to implement, e.g., integrated wavelength routers, lasers and sensors. The interaction of two or more optical modes by cascading multiple resonators leads to more sophisticated photonic applications through manipulation of the resonances and consequent flexible modification of the spectrum.
This dissertation investigates the potential benefits of a novel configuration of coupled resonators, which can act as photonic switching element, reflector and sensor. As opposed to previously reported coupled resonators, the proposed device consists of double MRRs that are indirectly coupled through a central bus waveguide and a crossing. This configuration, Indirectly Coupled Resonators (ICR), can carry out versatile photonic functions that are the subjects of the presented research. The studied devices were fabricated in two different integration technology platforms, the InP-membrane-on-silicon (IMOS) and Silicon-On-Insulator (SOI).
The wavelength routing properties of ICR are first examined in the context of the next generation Reconfigurable Optical Add/Drop Multiplexer (ROADM) for implementing flexible optical networks in wavelength division multiplexing technology. As a result of non-reciprocal wavelength routing behaviour, the ICR based switching fabric can combine the Add and Drop functions in a single transponder aggregator and therefore introduce bidirectional communication in ROADM systems that can reduce circuitry cost. Furthermore, the scalability analysis of an ICR based wavelength router topology is presented and compared with the conventional topology (λ-router) used in photonic Network-on-Chip applications. According to the topological analysis, ICR based routers can reduce the number of resonators required to construct such networks up to ∼ 50%, as the number of connected ports increases.
Then, the presented device is analysed considering its reflection properties. By performing phase synchronization of the two coupled resonators, it is possible to implement a wavelength reflector. The single wavelength reflection is experimentally demonstrated using the ICR fabricated in SOI technology. The critical conditions that exhibit such operational regimes are addressed. The measurements show that thermally detuned reflected wavelengths over a 37 nm of wavelength span can have very narrow bandwidths (∼ 50 pm), which correspond to quality factor of ∼ 30,000. Additionally, multiple wavelength reflections are also experimentally demonstrated by the racetrack ICR fabricated in IMOS technology.
Finally, a novel optical sensing scheme based on ICR is proposed. The scheme can execute data extraction from the sensor via either resonance shifts or intensity enhancements in the spectra of sensing signal relative to the reference signal. Therefore, this scheme is referred to as differential optical sensing. The differential sensing can pave the way of performing sensor calibration on-chip via an integrated heater on reference resonator. The performance comparison between conventional single ring and ICR based sensing schemes obtained from a suitably developed analytical model is presented.
Overall, the results presented in this thesis reveal the diverse capabilities of indirectly coupled resonators, mostly aiming at introducing a new building block for photonic integrated circuits.I continui progressi dell’ottica integrata e della fotonica consentono soluzioni alla avanguardia in campi di applicazione sempre più vasti. Le funzionalità dei Circuiti Fotonici Integrati (PIC) si arricchiscono continuamente grazie all'introduzione di nuovi elementi circuitali realizzati mediante dispositivi fotonici. Tra questi, i Risonatori ad Anello (Micro Ring Resonator - MMR) stanno suscitando un interesse particolare grazie alla loro vasta gamma di proprietà funzionali che possono servire per implementare, ad esempio, router, laser e sensori. L'interazione di queste funzionalità, ottenibile mediante la disposizione in cascata di più risonatori, porta ad applicazioni sempre più sofisticate, che sfruttano la manipolazione delle risonanze e la conseguente modifica flessibile dello spettro di trasmissione dei dispositivi così realizzati. Questa tesi propone un dispositivo innovativo basato su una particolare configurazione di risonatori accoppiati e ne analizza i potenziali benefici. Il dispositivo proposto può agire, a seconda della configurazione, come elemento di commutazione, come riflettore e come sensore. A differenza dei dispositivi proposti in letteratura basati su risonatori accoppiati direttamente, quello che viene presentato in questa tesi è costituito da una coppia di risuonatori interagenti in modo indiretto attraverso una guida d'onda. Questa topologia, definita come “Risonatori ad accoppiamento indiretto (Indirectly Coupled Resonators - ICR)”, grazie alla sua versatilità può svolgere funzionalità differenti, la cui indagine costituisce il tema portante di questa tesi. I dispositivi sviluppati in questi anni sono stati fabbricati utilizzando due piattaforme tecnologiche: InP-membrane-on-silicon (IMOS) e Silicon-On-Insulator (SOI). Il dispositivo proposto viene inizialmente analizzato quando configurato come router per reti ottiche flessibili (reti elastiche), in cui può essere impiegato come add/drop multiplexer riconfigurabile (ROADM). Grazie al comportamento non reciproco in lunghezza d’onda, questo dispositivo può combinare le funzioni di Add/Drop in un unico aggregatore bidirezionale. Viene poi presentata l’analisi della scalabilità e definita una tipologia di router per applicazioni nelle Network-on-chip ottiche. Secondo l'analisi topologica svolta in questa tesi, i router basati su topologie ICR possono ridurre fino al ∼ 50% il numero di risonatori necessari, a parità di numero di porte. Viene poi proposto l’utilizzo di tale dispositivo come riflettore ottenibile, a parità di topologia, eseguendo la sincronizzazione dei due risonatori. Le misure sono state effettuate con dispositivi fabbricati in tecnologia SOI e mostrano la possibilità di sintonizzare il riflettore in un range di lunghezze d’onda di 37 nm. Le riflessioni possono avere larghezze di banda molto strette (∼ 50 pm), corrispondenti ad un fattore di qualità di ∼ 30.000. La possibilità di ottenere riflessioni su lunghezze d’onda multiple è stata invece verificata utilizzando risonatori racetrack con raggi identici e fabbricati in tecnologia IMOS. Nell’ultima parte della tesi viene invece analizzato, attraverso l’utilizzo di modelli matematici, l’impiego di tale dispositivo in ambito sensoristico. Viene proposto uno schema di funzionamento differenziale, interrogabile in lunghezza d’onda ed in intensità. La tecnica differenziale impiegata consente l’esecuzione della calibrazione del dispositivo direttamente su chip, semplificando così la taratura dello stesso. Le prestazioni del sensore sono confrontate, attraverso modellizzazione numerica, con quelle di sensori risonanti convenzionali. I risultati presentati in questa tesi rivelano le molteplici proprietà dei risonatori accoppiati indirettamente, che possono dunque costituire un nuovo blocco funzionale per i circuiti integrati fotonici.
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Klinner-Teo, Teresa Deyi Maria. "Photonic circuits for exoplanet detection." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29765.
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The compelling scientific rewards for exoplanet detection in astronomy necessitates the development of imaging techniques able to explore parts of the parameter space unreachable by indirect methods: isolating planetary light for further investigation. Nulling interferometry is one of the most promising technologies for imaging exoplanets within stellar habitable zones. The Guided-Light Interferometric Nulling Technology (GLINT) instrument, the first multi-baseline photonic nulling interferometer, has explored the potential for photonics to deliver the performance to reach the realms of contrast and separation required for exoplanet detection in the near-infrared. GLINT highlights two key issues that limit current-generation photonic nullers: residual phase variations and chromaticity within the beam combiner. Both limitations are addressed by the use of tricouplers, which can deliver a broadband, achromatic null together with phase measurements for fringe tracking.
This thesis gives a derivation of the interactions of the tricoupler as the nuller’s core element, and presents designs for two devices to cancel on-axis light achromatically. A fully symmetric tricoupler is introduced, allowing a null signal to be delivered together with baseline-phase-dependent splitting into a pair of bright channels. Within some design trade space, the science signal or the fringe tracking ability can be prioritised. A phase shifter is also presented here, which can induce a phase shift of 180° with a variation of 0.6° in the 1.4-1.7μm band, producing a near-achromatic differential phase between beams. This functionality is required for optimal operation of the tricoupler nulling stage. Both devices can be integrated and replicated on a single photonic chip using ultrafast laser inscription, and can deliver a deep, broadband null together with a real-time fringe phase metrology signal.
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Wang, Ying. "Integrated photonic devices using self-assembled and optically defined photonic crystal superstructures." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3288723.
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Dainese, Matteo. "Plasma assisted technology for Si-based photonic integrated circuits." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148.
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Cho, Seong-Ho 1966. "Laser micromachining of active and passive photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/30086.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2004.Includes bibliographical references (leaves 149-158).
This thesis describes the development of advanced laser resonators and applications of laser-induced micromachining for photonic circuit fabrication. Two major advantages of laser-induced micromachining are direct patterning and writing on large areas of substrates at high speed following the exposure of laser light, without using complicated photomask steps. For passive photonic devices fabrication, a novel femtosecond laser with unprecedented low repetition rates of 4 MHz is demonstrated to generate high intensity pulses, as high as 1.25 MW with 100 nJ pulse energies and 80 fs pulse durations directly from this laser resonator, without using any active devices or amplifiers. These high intensity pulses are applied to transparent glass materials to demonstrate micromachining of waveguides, gratings, couplers, and three dimensional waveguides and their beam couplings. Active and passive semiconductor devices can be monolithically integrated by employing high energy laser pulses to locally disorder quantum well regions. The 45 nm bandgap shifts at 1.55 ptm with a standard Q-switched Nd:YAG laser at 535 nm are realized. Finally, unidirectional semiconductor ring lasers for high-density integration are developed as a potential application to photonic integrated circuits. Hybrid semiconductor S-crossover and retro-reflected ring lasers, as prototypes for unidirectional operation, are built and result in up to 21.5 dB and 24.5 dB of counter-mode suppression ratio, respectively, which is in good agreement with theoretical predictions.
by Seong-Ho Cho.
Ph.D.
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Prabhu, Mihika. "Towards optimal capacity-achieving transceivers with photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115725.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 63-65).
Optical communication systems have many advantages over communication systems that operate in the radio-frequency range, including decreased size, weight, and power consumption and increased bandwidth. As a result, optical communication systems are emerging as the ideal choice in many resource-constrained links such as those deployed on spacecraft. This thesis presents progress on development of a programmable nanophotonic processor (PNP) for implementing a high-fidelity reconfigurable optical transceiver at the telecommunications wavelength. By encoding information in multiple spatial modes and detecting jointly over the modes using a unitary transform prior to detection, one can in principle attain Holevo-limited channel capacity in the low mean photon number regime. Since the PNP offers dynamic reprogrammability, one can also, in principle, correct for wavefront distortion in the channel. We present a setup, calibration protocols, and preliminary results towards a turbulence-resistant integrated BPSK transmitter and joint detection receiver channel that achieves superadditive channel capacity in the low mean photon number regime.
by Mihika Prabhu.
S.M.
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Morgado, Tiago Manuel Coelho. "Photonic integrated circuits for use in NG-PON2 networks." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/18520.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesNos dias que correm com a adoção generalizada de smartphones, conteúdos de vídeo, computação em nuvem e redes sociais, o volume de tráfego não para de aumentar. Assim, existe uma procura constante para melhorar a largura de banda das redes existentes. Neste contexto surgiu a Next Generation Passive Optical Network Phase (NG-PON) 2 a qual é um novo standard que vai permitir um aumento da largura de banda que pode chegar aos 80Gbps. O conhecimento dos requisitos do standard NG-PON 2 é importante, para que se possam produzir equipamentos que possam vir a ser utilizados nestas redes. Atualmente existe uma grande evolução nas comunicações óticas. Esta evolução tecnológica levou ao aparecimento de Photonic Integrated Circuits(PICs). Os PICs permitem a integração no mesmo chip de diversos componentes óticos permitindo assim construir circuitos com maior desempenho e fiabilidade. Cada vez mais, existe um grande investimento nesta área, estão inclusivamente a aparecer softwares cujo propósito é permitir aos utilizadores criar e simular PICs, para que estes possam ser posteriormente construídos. É então importante o conhecimento das caraterísticas mais importantes dos blocos que estes softwares permitem simular. Neste trabalho serão testados alguns blocos do “VPItoolkit PDK HHI” que é um toolkit que quando adicionado no software VPItransmissionMaker™, permite simular os componentes produzidos pelo Heinrich Hertz Institute (HHI). Com estes componentes, serão ainda feitas simulações visando a sua utilização em uma rede NG-PON2. Foi também dada grande atenção ao estudo dos Multimode Interference Devices (MMI) dos quais foi feito um modelo em MATLAB. E ao mach Zehnder Modulator (MZM) do qual foi realizada uma animação a demostrar dinamicamente a propagação da Luz dentro dele. Foram ainda sugeridas duas arquiteturas possíveis para um tranceiver a ser utilizado no Optical Network Unit (ONU) em redes NG-PON 2.
Nowadays with the widespread adoption of smartphones, video content, cloud computing and social networks, the volume of traffic is constantly increasing. Therefore, it exists a constant demand to improve the bandwidth of the existing networks. In this context emerged the Next Generation Passive Optical Network Phase (NG-PON 2), which is a new standard that will allow an increase in the bandwidth up to 80 Gbps. The knowledge of the requirements of the standard NG-PON 2 is important, to allow the production of equipment that can be used in these networks. Currently there is a major evolution in optical communications. This technological evolution has led to the emergence of Photonic Integrated Circuits (PICs). By using PICs various optical components can be integrated on the same chip, allowing to build circuits with higher performance and reliability. Currently there is a large investment in this area, software whose purpose is to allow users to create and simulate PICs are starting to appear, to subsequently allow a correct manufacturing of the PICs. It is important to know the most important features of these software blocks and what do they allow to simulate. During this work some blocks from "VPItoolkit PDK HHI" will be tested. "VPItoolkit PDK HHI" is a toolkit that when added in VPItransmissionMaker ™ software allows the simulation of the components produced by the Heinrich Hertz Institute (HHI). With these components, simulations were made to test their use in a NG-PON2 network. It was also given attention to the study of the Multimode Interference Devices (MMI) from which was created a model in MATLAB. And to the Mach Zehnder Modulator (MZM) from which was made an animation to dynamically demonstrate the propagation of light inside him. It was also suggested two possible architectures for a transceiver to be used on the Optical Network Unit (ONU) in NG-PON 2 networks.
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Joshi, Siddharth. "Quantum dash based photonic integrated circuits for optical telecommunications." Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0031/document.
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Ce travail de thèse présente une étude sur les propriétés de nanostructures de type bâtonnets quantiques et de leur application pour les télécommunications optiques. Durant la dernière décennie, ces nanostructures, ont démontré des propriétés optiques et électroniques intéressantes en raison notamment d’un fort confinement quantique dans les trois dimensions d'espace. Cette thèse porte sur la conception et la fabrication d'émetteurs optiques intégrés à base de ce matériau et de leur implémentation dans des systèmes de communication. La première partie de ce travail analyse les propriétés de ces nanostructures, théorique et expérimentale. Elles sont utilisées comme matériau actif de lasers modulés directement en amplitude. Les propriétés dynamiques de ces lasers sont ensuite évaluées et des transmissions sur fibre optique entre 0 et 100 km sont ensuite démontrées en utilisant un filtre étalon permettant d’augmenter en particulier le taux d’extinction dynamique. En s’appuyant sur cette démonstration basée sur des éléments discrets, une version monolithique intégrant un laser et un résonateur en anneaux a été réalisée. La dernière partie de ce travail porte sur des lasers à blocage de mode à base de ce matériau et en particulier sur les méthodes d’intégration sur substrat InP. En particulier, un design de miroir de Bragg innovant a été développé à cet effet et une démonstration d'un laser a blocage de mode intégré avec un amplificateur optique à semi-conducteur a finalement été réaliséeThis PhD dissertation presents a study on the properties of the novel quantum dash nanostructures and their properties for application in optical telecommunications. Over the last decade, scientific community has gained considerable interest over these nanostructures and several demonstrations have been made on their interesting optical and electronic properties, notably owing to their strong quantum confinement. This dissertation focuses on conception, fabrication and system demonstration of integrated optical transmitters based on quantum dash material. A first part of this work analyses the properties of qdashes theoretically and experimentally for their use as an active material in directly modulated lasers. The dynamic properties of this material are then evaluated leading to an optical transmission distances in range of 0-100km under direct modulation. The transmission is particularly studied with a passive optical filter to enhance the dynamic extinction ratio, the use of such passive filters is studied in detail. An innovative and fully integrated optical transmitter is finally demonstrated by integrating a ring-resonator filter to a distributed feedback laser. The second part of this work focuses on mode locked lasers based on this material and in particular the methods of integration of such devices on InP are explored. Thus an innovative Bragg mirror design is developed leading to a mode locked laser integrated with a semiconductor optical amplifier
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Liu, Qiankun. "SiGe photonic integrated circuits for mid-infrared sensing applications." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS166/document.
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La spectroscopie dans le moyen-infrarouge est une méthode universelle pour identifier les substances chimiques et biologiques, car la plupart des molécules ont leurs résonances de vibration et de rotation dans cette plage de longueurs d'onde. Les systèmes moyen infrarouge disponibles dans le commerce reposent sur des équipements volumineux et coûteux, tandis que de nombreux efforts sont maintenant consacrés à la réduction de leur taille et leur intégration sur circuits intégrés. L’utilisation de la technologie silicium pour la réalisation de circuits photoniques dans le moyen-infrarouge présente de nombreux avantages: fabrication fiable, à grand volume, et réalisation de circuits photoniques à hautes performances, compacts, légers et à faible consommation énergétique. Ces avantages sont particulièrement intéressant pour les systèmes de détection spectroscopique moyen infrarouge, qui besoin d'être portable et à faible coût. Parmi les différents matériaux disponibles en photonique silicium, les alliages silicium-germanium (SiGe) à forte concentration en Ge sont particulièrement intéressants en raison de la grande fenêtre de transparence du Ge, pouvant atteindre 15 µm. Dans ce contexte, l'objectif de cette thèse est d'étudier une nouvelle plate-forme SiGe à forte concentration en Ge, pour la démonstration de circuits photoniques moyen infra rouge. Cette nouvelle plate-forme devrait bénéficier d'une large gamme de transparence en longueurs d'onde de transparence et de la possibilité d’ajuster les propriétés des guides optiques (indice effectif, dispersion,…). Au cours de cette thèse, différentes plates-formes basées sur différents profils graduels du guide d’onde ont été étudiées. Tout d'abord, il a été démontré qu’il était possible d’obtenir des guides présentant de faibles pertes optiques inférieures à 3 dB/cm dans une large plage de longueurs d'onde, de 5,5 à 8,5 µm. Une preuve de concept de détection de molécules, basée sur l'absorption de la partie évanescent du mode optique a ensuite été démontrée. Ensuite, les composants formant les briques de base classiques de la photonique intégrée ont été étudiés. Les premières cavités intégrées ont été réalisées à 8 µm. Deux configurations ont été étudiées : des cavité Fabry-Perot utilisant des miroirs de Bragg intégrés dans les guides d’onde et des résonateurs en anneau. Un spectromètre à transformée de Fourier fonctionnant sur une large bande spectrale, et pour les deux polarisations de la lumière a également été démontré. Tous ces résultats reposent sur la conception des matériaux et des composants, la fabrication en salle blanche et la caractérisation expérimentale. Ce travail a été effectué dans le cadre du projet européen INsPIRE en collaboration avec le Pr. Giovanni Isella de Politecnico Di MilanoMid-infrared (mid-IR) spectroscopy is a nearly universal way to identify chemical and biological substances, as most of the molecules have their vibrational and rotational resonances in the mid-IR wavelength range. Commercially available mid-IR systems are based on bulky and expensive equipment, while lots of efforts are now devoted to the reduction of their size down to chip-scale dimensions. The use of silicon photonics for the demonstration of mid-IR photonic circuits will benefit from reliable and high-volume fabrication to offer high performance, low cost, compact, lightweight and power consumption photonic circuits, which is particularly interesting for mid-IR spectroscopic sensing systems that need to be portable and low cost. Among the different materials available in silicon photonics, Germanium (Ge) and Silicon-Germanium (SiGe) alloys with a high Ge concentration are particularly interesting because of the wide transparency window of Ge up to 15 µm. In this context, the objective of this thesis is to investigate a new Ge-rich graded SiGe platform for mid-IR photonic circuits. Such new plateform was expected to benefit from a wide transparency wavelength range and a high versatility in terms of optical engineering (effective index, dispersion, …). During this thesis, different waveguides platforms based on different graded profiles have been investigated. First it has been shown that waveguides with low optical losses of less than 3 dB/cm can be obtained in a wide wavelength range, from 5.5 to 8.5 µm. A proof of concept of sensing based on the absorption of the evanescent component of the optical mode has then been demonstrated. Finally, elementary building blocs have been investigated. The first Bragg mirror-based Fabry Perot cavities and racetrack resonators have been demonstrated around 8 µm wavelength. A broadband dual-polarization MIR integrated spatial heterodyne Fourier-Transform spectrometer has also been obtained. All these results rely on material and device design, clean-room fabrication and experimental characterization. This work was done in the Framework of EU project INsPIRE in collaboration with Pr. Giovanni Isella from Politecnico Di Milano
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Jafarpour, Aliakbar. "Ultra Low-Loss and Wideband Photonic Crystal Waveguides for Dense Photonic Integrated Systems." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11598.
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This thesis reports on a new design of photonic crystal waveguides (PCWs) to achieve large guiding bandwidth, linear dispersion, single-mode behavior, good coupling efficiency to dielectric waveguides, and small loss. The design is based on using the linear dispersion region of one PCW in the photonic bandgap (PBG) of another PCW.
While perturbing the period can result in a PCW with linear dispersion and large guiding bandwidth, it introduces an odd mode at those frequencies, as well. By using another perturbation scheme, it is shown that single-mode behavior can also be achieved. The linear dispersion of these waveguides and their operation at lower frequencies of the PBG, where the density of states of radiation modes is smaller, gives rise to very small loss coefficients as verified experimentally.
Full characterization of a waveguide requires the measurement of not only the transmission coefficient, but also the dispersion and spectral phase. We have developed a real-time characterization technique based on spectral interferometry with femtosecond laser pulses at optical communication wavelengths to measure the spectral phase of waveguides. This haracterization technique can be used to study fast dynamics in timevarying structures and makes the alignment easy.
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Itawi, Ahmad. "Dispositifs photoniques hybrides sur Silicium comportant des guides nano-structurés : conception, fabrication et caractérisation." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112363/document.
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Le contexte de cette thèse couvre les dispositifs photoniques hybrides III-V sur silicium. L’étude porte sur l’intégration par collage de matériau à base d'InP sur le silicium, puis la conception d’un guide optique comportant une nanostructuration qui permettra la sélection en longueur d’onde dans un laser DFB hybride. Enfin, on étudie les étapes technologiques de fabrication d’un laser hybride injecté électriquement fonctionnant dans le domaine spectral 1.55µm, et on caractérise les dispositifs. Pour associer les matériaux III-V sur Si, nous avons développé le collage sans couche intermédiaire que l’on nomme collage hétéroépitaxial ou oxide-free. Ce collage est reporté dans la littérature comme présentant une meilleure qualité électrique. Nous avons établi les conditions de préparation permettant d’obtenir des surfaces parfaitement désoxydées, et les conditions de recuit conduisant à une interface hybride sans oxyde et sans dislocation. Mais ce recuit est réalisé à température assez élevée (~450-500°C). Nous avons alors développé le collage avec une fine couche intermédiaire d’oxyde réalisé à plus faible température -300°C- qui présente l'avantage d'être compatible avec la technologie CMOS. Nous avons étudié différentes approches pour élaborer et activer une couche d’oxyde très fine (~3nm), de façon à obtenir une surface collée sans zones localement non collées. Le collage est dans les deux cas réalisé sous vide dans un équipement de type Bonder Suss SB6e. La qualité structurale de l’interface a été observée par STEM et la qualité mécanique du joint de collage a été caractérisée par indentation. Une méthode originale de mesure quantitative et locale de l’énergie du joint de collage a été développée. La qualité optique des couches collées a été étudiée par la mesure de la photoluminescence de puits quantiques placés proches du joint d’interface. En conséquence du collage sans couche intermédiaire ou avec une couche très fine, le design du mode optique est de type double-cœur, qui ne nécessite pas de taper. Le guide optique Si est de type shallow ridge, le confinement latéral étant assuré par un matériau nanostructuré à une période sub-longueur d’onde. Ce matériau fonctionne comme un matériau effectif uniaxe pour lequel on a calculé les indices optiques ordinaire et extraordinaire selon la géométrie de la nanostructuration. On peut rajouter sur cette nanostructuration une super-périodicité qui conduit à un fonctionnement sélectif en longueur d’onde. Le comportement modal du guide est simulé à l'aide du logiciel COMSOL Multiphysics, le comportement spectral est simulé par FTDT 3D. Nous avons validé la pertinence de ce design en mesurant la transmission de guides hybrides. Ce design sera inclus dans un laser et permettra d’obtenir une émission monofréquence de type DFB. Nous avons développé les étapes technologiques nécessaires à la fabrication d’un laser hybride à base d'InP sur Silicium fonctionnant en injection électrique. Nous avons mis en oeuvre de nombreuses techniques, et développé plusieurs procédés spécifiques, en particulier, des procédés de gravure sèche de type Inductive Coupled Plasma Reactive Ion Etching ICP-RIE pour la gravure de la nanostructuration dans le silicium, et pour la gravure du mésa du laser. La présence des 2 matériaux III-V et Si dans le dispositif hybride rend ces étapes complexes. Les premiers résultats peuvent être améliorés en optimisant la technologie des contacts. Un design permettant de s’affranchir de la pénalité thermique présenté par tous les dispositifs ayant les 2 contacts électriques du coté du matériau III-V a été proposé, exploitant le passage du courant à l’interface hybride III-V / Si, ce qui est possible dans le cas du collage oxide-free. Cette approche ouvre des perspectives d’intégration au-delà de la photoniqueThis work contributes to the general context of III-V materials on Silicon hybrid devices for optical integrated functions, mainly emission/amplification at 1.55µm. Devices are considered for operation under electrical injection, reaching performances relevant for data transfer application. The main three contributions of this work concern: (i) bonding InP-based materials on Si, (ii) nanostructuration of the Si guiding layer for spatial and spectral control of the guided mode and (iii) technology of an hybrid electrically injected laser, with a special attention to the thermal budget. Bonding has been investigated following two approaches. The first one we call heterohepitaxial or oxide-free bonding, is performed without any intermediate layer at a temperature ~450°C. This approach has the great advantage allowing electrical transport across the interface, as reported in the literature. We have developed oxide-free surface preparation for both materials, mainly InP-based layers, and established bonding parameter processing. An in-depth STEM and RX structural characterization has demonstrated an oxide-free reconstructed interface without any dislocation except on one or two atomic layers which accommodate the large lattice mismatch (8.1%) between InP and Si. Photoluminescence of quantum wells intentionally grown close to the interface has shown no degradation. We have also developed an oxide-based bonding process operated at 300°C in order to be compatible with CMOS processing. The original ozone activation of the very thin (~5nm) oxide layer we have proposed demonstrates a bonding surface without any unbonded area due to degassing under annealing. We have developed an original method based on nanoindentation characterization in order to obtain a quantitative and local value of the surface bonding energy. Related to the absence or to the very thin intermediate layer between the two materials, our modal design is based on a double core structure, where most of the optical mode is confined in the Si guiding layer, and no taper is required. The Si waveguide on top of the SOI stack is a shallow ridge. A nanostructured material on both sides of the waveguide core ensures the lateral confinement, the nanostructuration geometry being at a sub-wavelength period in order to operate this material well below its photonic gap. It behaves as an uniaxial material with ordinary and extraordinary indices calculated according to the structuration geometry. Such a structuration allows modal and spectral control of the guided mode. 3D modal and spectral simulation have been performed. We have demonstrated, on a double-period structuration, a wavelength selective operation of hybrid optical waveguides. Such a double-period geometry could be included in a laser design for DFB operation. This nanostructuration has larger potential application such as coupled waveguides arrays or selective resonators. We have developed all the technological processing steps for an electrically injected hybrid laser fabrication. Main developments concern dry etching, performed with the Inductive Coupled Plasma Reactive Ion Etching ICP-RIE technique of both the nanostructuration of the Silicon material, and the mesa of the hybrid laser. Efficient electrical contacts fabrication is also a complex step. First lasers operating performances could be improved. We have investigated a specific design in order to overcome the thermal penalty encountered by all the hybrid devices. This penalty is due to the thick buried oxide layer of the SOI stack that prevents heating related to the current flow to be dissipated. Taking advantage of the electrical transport we have shown at the oxide-free interface, we propose a design where the n-contact is defined on the guiding Si layer, suppressing thermal heating under electrical operation. Such an approach is very promising for densely packed hybrid devices integrated with associated electronic driving elements on Si
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Korn, Dietmar [Verfasser]. "Silicon-Organic Hybrid Platform for Photonic Integrated Circuits / Dietmar Korn." Karlsruhe : KIT Scientific Publishing, 2015. http://www.ksp.kit.edu.
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Greenspan, Jonathan. "Selective area epitaxy for indium phosphide based photonic integrated circuits." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82883.
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The ability to integrate multiple photonic devices on a single substrate has turned out to be very advantageous in the fabrication of components for optical communication networks. For example, improved fiber coupling can be achieved by integrating a modulator with an optical mode converter. However, current technology is very limited in its ability to fabricate such photonic integrated circuits (PIC).We report on a selective area epitaxy (SAE) process suitable for the fabrication of a PIC. The process includes a quantitative model, which for the first time, is capable of predicting the growth rate and composition of thin films selectively deposited by metalorganic chemical vapour deposition in areas close to the dielectric mask as well as areas several microns away. The accuracy of the model is demonstrated by comparing simulation results with experimental measurements of the thickness and composition profiles obtained by surface profilometry and energy dispersed X-ray respectively.
The process is applied to the fabrication of an elecroabsorption modulator and optical mode converter, monolithically integrated on an InP substrate. As part of the fabrication, quantitative modeling of the converter waveguide core deposition is employed to achieve a thickness profile previously designed by beam propagation calculations. Modeling is also used to predict the composition and strain shifts introduced by selective deposition, enabling the composition to be designed such that the maximum strain is minimized. Device measurements demonstrate that SAE is successfully used for the fabrication of a PIC with characteristics superior to those found in conventional devices.
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Cemlyn, Benjamin R. "Dynamics of tunable lasers in small-scale photonic integrated circuits." Thesis, University of Essex, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605150.
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Mutually coupled lasers have received much attention in recent years as a source of rich non linear dynamics, enabling optical configurations for new ranges of applications, particularly chaos-based encrypted communications. However the overall dynamics of the mutually coupled configuration has not received so much attention, particularly with regard to the practical range of parameters for the lasers. This thesis investigates the dynamics of the mutually coupled lasers system in respect of all the significant causes and influences on dynamics. Furthermore, the lasers here are widely tuneable, representing the more complex tunable devices found in modern communications systems. The system investigated is both self and mutually-coupled, which represents the mechanism which may arise in modern photonic integrated circuits (PICs), and therefore has relevance to the design and operation of such devices. However the configuration here has parallels with, and great relevance to the non self-coupled configuration, and the conditions for this (such as phase) are highlighted. The dynamics are investigated experimentally in an integrated device using some of the latest technology to obtain time series of a high bandwidth, in addition to optical spectra and high resolution radio-frequency spectra. These enable a range of dynamic analysis tools such as the correlation dimension (for which a unique algorithm is described) to be applied, and this provides insight into the dynamics of the system. The PIC is also modelled using a thorough and realistic travelling wave method, which is required for the complex system of multiple coupling sources, with varying delays and optical paths which may be found in modem PICs. The PIC parameters such as coupling magnitude are first investigated experimentally and then various methods are used to calibrate these relations within the travelling wave program. A number of tuning properties of the OBR laser(s) within the PIC are then given in both the model and experiment, with good correlation between the two found. The principal investigations of dynamics in the PIC are then described. This commences with details of the overall dynamics of the PIC, and the dynamic analysis tools required to represent and quantify these dynamics. The effects of varying coupling between the lasers over a range of frequency detuning values are then studied. The effects of coupling magnitude are quantified with respect to an overall transition to chaos in the system, and overall dynamic trends. Correlation is found between the experimental and modelled results. The system of phases in the PIC are then investigated, and this has impact on the permutations of phase between oscillators in respect of conditions such as spatial symmetry and index dispersion. The control of the system of phases as a single ensemble is then described, and this is found to produce a rich variety of dynamic behaviour from this subtle parameter. Phase controlled dynamics are demonstrated experimentally, and correlated dynamics in the model are demonstrated. Finally four wave mixing, which is present in many optical configurations is shown to have a profound effect on dynamics in the model, and experimental results are presented supporting these results. These parameters of coupling magnitude, detuning, phase and four wave mixing level represent the major contributing causes of dynamics in multi-laser PICs. The results presented here have implications for the design and use of PICs, either to exploit or avoid these dynamics.
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Yang, Zhen. "Photonic integrated circuits for high speed sub-terahertz wireless communications." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708677.
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Holzwarth, Charles W. III (Charles Willett). "Material selection and nanofabrication techniques for electronic photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53248.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 149-154).
Electronic-photonic integrated circuits have the potential to circumvent many of the performance bottlenecks of electronics. To achieve the full benefits of integrating photonics with electronics it is generally believed that wavelength-division multiplexing is needed; requiring an integrated optical device capable of multiplexing/demultiplexing operations. One such device is a bank of microring-resonator filters with precisely spaced resonant frequencies. In this work, a fabrication strategy based on scanning-electron-beam lithography (SEBL) is presented for precisely controlling the resonant frequency of microring-resonator filters. Using this strategy it is possible to achieve dimensional control, on the tens-of- picometer scale, as required for microring-resonator filter banks. To correct for resonant-frequency errors present after fabrication, two forms of postfabrication tuning, one dynamic and one static, are demonstrated. It is also shown that hydrogen silsesquioxane (HSQ) can be converted into a high-quality overcladding for photonic devices by optimizing the annealing process. Finally, a postfabrication technique of localized substrate removal is presented, enabling the integration of photonics with CMOS electronics. Second-order microring-resonator filter banks were fabricated using SiNx and Si as the high -index core materials. By controlling the electron-beam-exposure dose it is possible to change the average microring-waveguide width to a precision better than 75 pm, despite the 6 nm SEBL address grid. Using postfabrication tuning the remaining resonant-frequency errors can be reduced to less than 1 GHz.
(cont.) By annealing HSQ in a an 02 atmosphere using rapid thermal processing, it is possible to create thick overcladding layers that have essentially the same optical properties as SiO2 with the excellent gap-filling and planarization properties of HSQ. Using XeF2 to locally etch an underlying Si substrate, waveguides with a propagation loss of -10 dB/cm were fabricated out of polysilicon deposited on 50 nm of SiO2.
by Charles W. Holzwarth, Ill.
Ph.D.
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Ferreira, Ana Rita Rodrigues. "Photonic integrated circuits development: a universal transceiver for NG-PON2." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15974.
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Mestrado em Engenharia Eletrónica e TelecomunicaçõesIn the last years there has been a clear evolution in the world of telecommunications, which goes from new services that need higher speeds and higher bandwidth, until a role of interactions between people and machines, named by Internet of Things (IoT). So, the only technology able to follow this growth is the optical communications. Currently the solution that enables to overcome the day-by-day needs, like collaborative job, audio and video communications and share of les is based on Gigabit-capable Passive Optical Network (G-PON) with the recently successor named Next Generation Passive Optical Network Phase 2 (NG-PON2). This technology is based on the multiplexing domain wavelength and due to its characteristics and performance becomes the more advantageous technology. A major focus of optical communications are Photonic Integrated Circuits (PICs). These can include various components into a single device, which simpli es the design of the optical system, reducing space and power consumption, and improves reliability. These characteristics make this type of devices useful for several applications, that justi es the investments in the development of the technology into a very high level of performance and reliability in terms of the building blocks. With the goal to develop the optical networks of future generations, this work presents the design and implementation of a PIC, which is intended to be a universal transceiver for applications for NG-PON2. The same PIC will be able to be used as an Optical Line Terminal (OLT) or an Optical Network Unit (ONU) and in both cases as transmitter and receiver. Initially a study is made of Passive Optical Network (PON) and its standards. Therefore it is done a theoretical overview that explores the materials used in the development and production of this PIC, which foundries are available, and focusing in SMART Photonics, the components used in the development of this chip. For the conceptualization of the project di erent architectures are designed and part of the laser cavity is simulated using Aspic™. Through the analysis of advantages and disadvantages of each one, it is chosen the best to be used in the implementation. Moreover, the architecture of the transceiver is simulated block by block through the VPItransmissionMaker™ and it is demonstrated its operating principle. Finally it is presented the PIC implementation.
Nos últimos anos tem existido uma evidente evolução no mundo das telecomunicações, que vai desde novos serviços que requerem maiores velocidades e maior largura de banda, a um role de interações entre pessoas e máquinas, designada por Internet of Things (IoT). Assim, a única tecnologia capaz de acompanhar este crescimento são as comunicações óticas. Atualmente a solução que permite colmatar as necessidades do dia-a-dia, tais como trabalhar colaborativamente, comunicar por áudio e vídeo, e partilhar ficheiros, é baseada no Gigabit-capable Passive Optical Network (G-PON) com a mais recente evolução designada por Next Generation Passive Optical Network Phase 2 (NG-PON2). Esta tecnologia baseia-se na multiplexagem no domínio do comprimento de onda e devido às suas características e desempenho torna-se a tecnologia mais vantajosa. Um dos principais focos das comunicações óticas são os Photonic Integrated Circuits (PICs). Estes conseguem englobar num único dispositivo vários componentes, o que simplifica o desenho do sistema ótico, reduzindo o espaço e o consumo de energia e melhora a confiabilidade. Estas caracteristicas tornam este tipo de dispositivos vantajosos para uma série de aplicações, justificando os investimentos no desenvolvimento da tecnologia para um nível muito elevado de desempenho e fiabilidade ao nível dos blocos de construção. Com o objetivo de desenvolver as redes óticas passivas de futuras gerações, este trabalho apresenta o desenho e a implementação de um PIC que visa ser um transrecetor universal para aplicações para NG-PON2. O mesmo PIC pode ser usado como Optical Line Terminal (OLT) ou como Optical Network Unit (ONU) e em ambos os casos como transmissor e recetor. Inicialmente é feito um estudo das redes óticas passivas e os seus standards. Seguidamente é feita uma abordagem teórica que explora um pouco dos materiais usados no desenvolvimento e produção de um PIC, quais as fábricas existentes, focando na SMART Photonics e os componentes usados no desenvolvimento deste chip. Com vista à concetualização do projeto, diferentes arquiteturas são desenhadas e a parte da cavidade do laser é simulada usando o Aspic™. Partindo da análise das vantagens e desvantagens de cada uma delas, é escolhida a melhor para utilizar na implementação. De seguida, a arquitetura do transrecetor é simulada bloco a bloco através do VPItransmissionMaker™ e é demonstrado o seu princípio de funcionamento. Finalmente é apresentada a implementação do PIC.
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Tsvirkun, Viktor. "Optomechanics in hybrid fully-integrated two-dimensional photonic crystal resonators." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112176/document.
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Les systèmes optomécaniques, dans lesquels les vibrations d'un résonateur mécanique sont couplées à un rayonnement électromagnétique, ont permis l'examen de multiples nouveaux effets physiques. Afin d'exploiter pleinement ces phénomènes dans des circuits réalistes et d'obtenir différentes fonctionnalités sur une seule puce, l'intégration des résonateurs optomécaniques est obligatoire. Ici nous proposons une nouvelle approche pour la réalisation de systèmes intégrés et hétérogènes comportant des cavités à cristaux photoniques bidimensionnels au-dessus de guides d'ondes en silicium-sur-isolant. La réponse optomécanique de ces dispositifs est étudiée et atteste d'un couplage optomécanique impliquant à la fois les mécanismes dispersifs et dissipatifs. En contrôlant le couplage optique entre le guide d'onde intégré et le cristal photonique, nous avons pu varier et comprendre la contribution relative de ces couplages. Cette plateforme évolutive permet un contrôle sans précédent sur les mécanismes de couplage optomécanique, avec un avantage potentiel dans des expériences de refroidissement et pour le développement de circuits optomécaniques multi-éléments pour des applications tels que le traitement du signal par effets optomécaniquesOptomechanical systems, in which the vibrations of a mechanical resonator are coupled to an electromagnetic radiation, have permitted the investigation of a wealth of novel physical effects. To fully exploit these phenomena in realistic circuits and to achieve different functionalities on a single chip, the integration of optomechanical resonators is mandatory. Here, we propose a novel approach to heterogeneously integrated arrays of two-dimensional photonic crystal defect cavities on top of silicon-on-insulator waveguides. The optomechanical response of these devices is investigated and evidences an optomechanical coupling involving both dispersive and dissipative mechanisms. By controlling optical coupling between the waveguide and the photonic crystal, we were able to vary and understand the relative strength of these couplings. This scalable platform allows for unprecedented control on the optomechanical coupling mechanisms, with a potential benefit in cooling experiments, and for the development of multi-element optomechanical circuits in the frame of optomechanically-driven signal-processing applications
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Koch, Thomas L., Michael Liehr, Douglas Coolbaugh, John E. Bowers, Rod Alferness, Michael Watts, and Lionel Kimerling. "The American Institute for Manufacturing Integrated Photonics: advancing the ecosystem." SPIE-INT SOC OPTICAL ENGINEERING, 2016. http://hdl.handle.net/10150/621540.
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The American Institute for Manufacturing Integrated Photonics (AIM Photonics) is focused on developing an end- to- end integrated photonics ecosystem in the U.S., including domestic foundry access, integrated design tools, automated packaging, assembly and test, and workforce development. This paper describes how the institute has been structured to achieve these goals, with an emphasis on advancing the integrated photonics ecosystem. Additionally, it briefly highlights several of the technological development targets that have been identified to provide enabling advances in the manufacture and application of integrated photonics.
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Samadian, Parya. "Photonic Integrated Circuits Challenges & Solutions: Homogenization, Polarization Management and Coupling." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33352.
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In recent years much effort has been carried out to make integrated photonics a widespread technology to be exploited in current optical communication industry. It is hoped
by substituting microelectronics by photonic chips and keeping the light carried by
optical fibers in light domain for further processing, the cost and speed of
communications will be vastly improved. Although this transition is challenging in
various aspects, here in this thesis some of these issues are discussed and addressed.
In this thesis firstly the limitations of current simulation tools for analysis of wide range
of photonic devices is pointed out. Structures based on photonic crystals are taken into
consideration at this point which because of finely detailed structures have shown to be
challenging to be analyzed by conventional tools. In this regard three different common
structures based on photonic crystals in both resonant and non-resonant regimes have
been considered: lamellar gratings, metamaterials for Lüneburg lens and Bragg gratings
in a LC-DFB laser. For each structure, an analytical method or homogenization approach
is proposed which is claimed to be faster for analysis of such components than numerical
methods. Comparisons of the results with conventional numerical methods prove
accuracies of each approach.
Furthermore, fiber-to-chip coupling and polarization management are discussed as other
important issues in the field of integrated photonics. Concerning polarization
management, stepped waveguide approach will be introduced as the most promising
approach for SOI and III-V substrates and designs based on this structure reported in
literature are reproduced and inaccuracies are pointed out and corrected accordingly. Also
regarding fiber-to-chip coupling, a critical appraisal of the most recent proposed
structures for edge coupling will be offered and the results will be reproduced by
simulation tools. At the end, based on detailed comparisons, the most encouraging
approach with low insertion loss and easy fabrication steps is introduced and novel
platform for easy butt coupling single mode fibers to the coupler structure is proposed.
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Cegielski, Piotr [Verfasser]. "Development of Integrated Perovskite Lasers for Dielectric Photonic Circuits / Piotr Cegielski." München : Verlag Dr. Hut, 2019. http://d-nb.info/1198542934/34.
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Bishop, Zofia Katarzyna. "III-V semiconductor nano-photonic devices for integrated quantum optical circuits." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/22613/.
Full textAbstract:
The work presented in this thesis is motivated by the ultimate goal of realizing a fully integrated quantum optical circuit (IQOC), based on a III-V semiconductor, specifically gallium arsenide (GaAs), in a planar architecture with embedded indium arsenide (InAs) quantum dots as single photon sources. Technological challenges involved with achieving a scalable quantum photonic circuit are addressed through the design, development and testing of controllable on-chip nano-photonic elements, such as nanobeam photonic crystal filters and electro-mechanical actuators. The research into both of these types of devices presented here represents the first work of this kind that has been carried out in the LDSD group at the University of Sheffield. The majority of the measurements that have been undertaken and which are presented here are of an optical spectroscopic nature. An on-chip optical filter based on a one-dimensional photonic crystal structure has been modelled and demonstrated experimentally. Such devices can be integrated with other circuit elements in order to achieve a purely electrically driven IQOC. Tuning the resonant wavelength of the device in order to attain control over the filtering parameters has also been investigated. Control over the splitting ratio of an on-chip optical beam splitter operating at the single photon level has been achieved through an electro-mechanical cantilever based system for the first time on the GaAs platform. This technology, which can be used for switching and phase shifting, now paves the way towards the physical realization of reconfigurable IQOCs. Other more efficient and versatile electro-mechanical systems that could be used to provide greater control over a variety of optical circuit elements, such as filters and beam splitters, have also been investigated experimentally. Comb-drive actuators, which are well established on silicon based platforms, have been developed for use in the GaAs based quantum optical architecture.
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Zhu, Di S. M. Massachusetts Institute of Technology. "Superconducting nanowire single-photon detectors on aluminum nitride photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108974.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 85-91).
With recent advances in integrated single-photon sources and quantum memories, onchip integration of high-performance single-photon detectors becomes increasingly important. The superconducting nanowire single-photon detector (SNSPD) is the leading single-photon counting technology for quantum information processing. Among various waveguide materials, aluminum nitride (AlN) is a promising candidate because of its exceptionally wide bandgap, and intrinsic piezoelectric and electro-optic properties. In this Master's thesis, we developed a complete fabrication process for making high-performance niobium nitride SNSPDs on AlN, and demonstrated their integration with AlN photonic waveguides. The detectors fabricated on this new substrate material have demonstrated saturated detection efficiency from visible to near-IR, sub-60-ps timing jitter, and ~6 ns reset time. This work will contribute towards building a fully integrated quantum photonic processor.
by Di Zhu.
S.M.
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Goldstein, Jordan (Jordan A. ). "Large-scale integration of graphene optoelectronic devices in photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106019.
Full textAbstract:
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 55-59).
Graphene is a 2D material recognized for its extremely high mobility and novel optoelectronic properties. In this thesis, we argue in favor of integrating graphene as an active optoelectronic material alongside optical waveguides on the back-end of CMOS ICs for photonic links in access network and computing applications. We describe a simple fabrication process which can accommodate both graphene modulators and photodetectors on almost any waveguide platform. We use this process to fabricate such devices on silicon waveguides and provide preliminary measurements. Finally, we discuss further research opportunities to improve graphene modulators and detectors to the point of being a competitive technology.
by Jordan Goldstein.
M. Eng.
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Gan, Fuwan. "High-speed silicon electro-optic modulator for electronic photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40498.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.Includes bibliographical references (p. 173-184).
The development of future electronic-photonic integrated circuits (EPIC) based on silicon technology critically depends on the availability of CMOS-compatible high-speed modulators that enable the interaction of electronic and optical signals. This thesis investigates electrically driven Mach-Zehnder modulators based on high-index contrast silicon waveguide technology and electronic carrier injection. Modulators based on four different structures are investigated: the forward-biased PiN diode with and without lifetime reduction, the reverse-biased PIN/PN diode and a metal-oxide-semiconductor (MOS) structure. These devices are compared with each other in terms of achievable performance. A modulator based on the forward-biased PIN diode with lifetime reduction is designed to reach 34GHz bandwidth and a low figure of merit V -. L = 0.6V - cm using a carrier lifetime reduction and a graded doping profile. A bandwidth of 1-2GHz has been demonstrated so far which is considerably smaller than the design bandwidth due to high series resistance. Modulators based on the forward-biased PIN structure without lifetime reduction have a low figure of merit, very low voltage and extremely low power consumption in the low frequency regime.
(cont.) The measurements demonstrate a RF power consumption of 100mW for 25% modulation depth and a figure of merit of V, - L = 0.28V - cm at frequencies up to 10GHz. A pre-compensation technique, using a high pass filter which consists of a parallel resistor and capacitor, extends the modulator bandwidth from 100MHz to 5GHz experimentally. Further it is shown that, modulators based on the reverse-biased structure can in principle reach very high speed, up to 40-80GHz in design but it's difficult to reduce V, - L values close to or even below 1V - cm and the necessary drive voltage is higher than the voltage provided by the CMOS technology. For the measured bandwidth of the fabricated devices so far only 1-2GHz has been demonstrated. This discrepancy is caused by the RC delay due to the experimental setup and high contact resistance. Finally, the performance of the modulator based on the metal-on-semiconductor (MOS) structure is analyzed. Furthermore, an electrically driven Mach-Zehnder waveguide modulator based on a high-index contrast silicon split-ridge waveguide (SRW) technology and electronic carrier injection is proposed.
(cont.) The excellent optical and carrier confinement possible in high-index contrast waveguide devices, together with the forward biased operation and the good thermal heat sinking due to the silicon slab close to the waveguide, enables high speed modulation with small signal modulation bandwidths beyond 20GHz, a V, times length figure of merit of V, - L = 0.5Vcm and an insertion loss of about 5.3 dB. Finally, all-optical switches based on optical carrier-injection in high index contrast Si/Si02 split-ridge-waveguide (SRW) couplers are proposed. The waveguide devices are suitable for the construction of low-loss optical switch matrices as well as fast optical switching. These devices exhibit robustness against fabrication tolerances, improved heat sinking, good carrier confinement and high uniformity in transmission over the entire C-band of optical communications in contrast to comparable devices based on buried or ridge waveguides. A reasonably low electrical switching power of 1-10mW is predicted for switching frequencies in the 1MHz-1GHz range. Faster switching speed can be achieved by carrier lifetime reduction.
by Fuwan Gan.
Ph.D.
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Aghajani, Armen. "Waveguide lasers in ytterbium doped tantalum pentoxide for integrated photonic circuits." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/388523/.
Full textAbstract:
This thesis investigates ytterbium doped tantalum pentoxide as a material system for realising waveguide lasers on silicon substrate, as a basis to provide the next generation of mass-producible, low-cost planar devices with many interlocking photonic circuits for multi-functionality. Numerical modelling of symmetrical rib waveguide in Ta2O5 was carried out finding an optimum waveguide design for a near-circular mode profile with maximum confinement of light within the core with various etch depths and rib widths. A numerical study investigating the feasibility of integrated Kerr lens elements for future mode-locking was carried out, predicting that a Kerr lens slab with a length of 20 μm with input and out waveguides was able to achieve a 9% modulation depth for input intensity of 6 GW/m2. Thin films were fabricated by RF magnetron sputtering onto a silicon substrate with 2.5 μm silica layer from a powder pressed Yb:Ta2O5 target, with shallow rib waveguides realised using photolithography and ion beam milling. The excited-state lifetime of Yb:Ta2O5 was measured to be 0.25 ± 0.03 ms, and peak emission and absorption cross-sections were determined to be 2.9 ± 0.7×10-20 cm2 and 2.75 ± 0.2×10-20 cm2 respectively, with the fluorescence spectrum giving a broadband emission from 990 nm to 1090 nm. Finally a 10.8 mm long waveguide laser in Ta2O5 doped with ≈ 6.2×1020 Yb atoms/cm3 of ytterbium oxide was demonstrated with a laser cavity formed from a combination of high reflective mirrors with output couplers or reflections from the bare end-facets with Fresnel reflectivity of 12%. In a 5.4 μm wide waveguide, lasing was observed between 1015 nm and 1030 nm when end-pumped with a 977 nm laser diode with the highest output power of 25 mW at a wavelength of 1025 nm with an absorbed pump power of 120 mW for a cavity formed by a high reflector mirror and a bare end-facet at the output. In this case, the absorbed pump power threshold and slope efficiency were measured to be ≈ 30 mW and ≈ 26% respectively. The results presented in this thesis demonstrate that tantalum pentoxide has great potential for mass-producible, integrated optical circuits on silicon using conventional CMOS fabrication technologies.
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Burrow, Guy Matthew. "Pattern-integrated interference lithography: single-exposure formation of photonic-crystal lattices with integrated functional elements." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44804.
Full textAbstract:
A new type of photolithography, Pattern-Integrated Interference Lithography (PIIL), was demonstrated. PIIL is the first-ever integration of pattern imaging with interference lithography in a single-exposure step. The result is an optical-intensity distribution composed of a subwavelength periodic lattice with integrated functional circuit elements. To demonstrate the PIIL method, a Pattern-Integrated Interference Exposure System (PIIES) was developed that incorporates a projection imaging capability in a novel three-beam interference configuration. The purpose of this system was to fabricate, in a single-exposure step, representative photonic-crystal structures. Initial experimental results have confirmed the PIIL concept, demonstrating the potential application of PIIL in nano-electronics, photonic crystals, biomedical structures, optical trapping, metamaterials, and in numerous subwavelength structures. In the design of the PIIES configuration, accurate motif geometry models were developed for the 2D plane-group symmetries possible via linearly-polarized three-beam interference, optimized for maximum absolute contrast and primitive-lattice-vector direction equal contrast. Next, a straightforward methodology was presented to facilitate a thorough analysis of effects of parametric constraints on interference-pattern symmetries, motif geometries, and their absolute contrasts. With this information, the design of the basic PIIES configuration was presented along with a model that simulates the resulting optical-intensity distribution at the system sample plane. Appropriate performance metrics were defined in order to quantify the characteristics of the resulting photonic-crystal structure.
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Liu, Jifeng Ph D. Massachusetts Institute of Technology. "GeSi photodetectors and electro-absorption modulators for Si electronic-photonic integrated circuits." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/38582.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.Includes bibliographical references (p. 185-188).
The silicon electronic-photonic integrated circuit (EPIC) has emerged as a promising technology to break through the interconnect bottlenecks in telecommunications and on-chip interconnects. High performance photonic modulators and photodetectors compatible with Si complimentary metal oxide semiconductor (CMOS) devices are indispensable to achieve this goal. A photonic modulator generates optical "1" and "0" signals by switching the light on and off, while a photodetector converts the optical signals to electrical ones so that they can be processed by a CMOS circuit. Due to its compatibility with Si CMOS processing and adequate optoelectric properties, epitaxial GeSi material has been considered as a promising candidate to achieve this goal. This thesis investigates epitaxial GeSi photodetectors and electro-absorption (EA) modulators integrated with high index contrast Si(core)/Si02(cladding) waveguides to form an EPIC circuit on a Si platform with CMOS compatibility. Tensile strain is introduced into the GeSi material to enhance its optoelectronic properties. The effect of tensile strain on the band structure of Ge is systematically studied, and the deformation potential constants of Ge are derived from the experimental results with relatively high accuracy.
(cont.) Methods to engineer the tensile strain in Ge are demonstrated. Tensile strain in small, selectively grown Ge mesas and stripes with at least one dimension <<10 jim is also investigated. The results are instructive to design selectively grown GeSi EA modulators and photodetectors integrated with Si/SiO2 waveguides. Free-space coupled Ge photodetectors on Si are fabricated with significantly improved performance in the L band (1561-1620nm) of telecommunications as a result of strain engineering. We have demonstrated a selectively grown Ge photodetector on a Si platform with a bandwidth of 8.5 GHz and a high responsivity over a broad wavelength range of 650-1605 nm. Full responsivity was achieved at 0 bias and full bandwidth was obtained at 1 V reverse bias, compatible with the requirement of Si ultra-large scale integrated circuits (ULSI). The GeSi EA modulator is based on Franz-Keldysh (FK) effect, where the electric field shifts the direct band edge of the GeSi material and significantly enhances its absorption coefficient in the weakly absorbing regime. Therefore, by modulating the electric field in the GeSi material, we can modulate the intensity of the light of a certain range of wavelength that passes through the GeSi material. A strain-enhanced FK effect in tensile strained epitaxial Ge material is demonstrated.
(cont.) A waveguide-integrated GeSi EA modulator with 4.8 dB insertion loss, 9.8 dB extinction ratio and a bandwidth >50 GHz has been designed with the material composition and device structure optimized for operations around 1550 nm. The same material and device structure can be also used for waveguide-integrated photodetectors with a responsivity of 1.1 A/W at 1550 nm and a bandwidth >35 GHz. A method to monolithically integrate GeSi modulators, photodetectors and Si/SiO2 waveguides is proposed and the expected performance is evaluated. Waveguide-integrated GeSi photodetectors and EA modulators are fabricated on a standard 180 nm CMOS production line based on the design. We demonstrate a waveguide-integrated GeSi photodetector with a responsivity of 1.0 A/W at 1518 nm and a bandwidth >4.5 GHz, as well as a GeSi EA modulator with an extinction ratio of -0.3 dB. While the device performance of the EA modulator is far from ideal due to fabrication issues, the preliminary results demonstrate the feasibility of the electronic-photonic integration on a Si platform with GeSi modulator and detector devices. The problems in this first device processing are identified, and solutions are proposed and partially tested. The device performance could be greatly enhanced with improved processing technique.
by Jifeng Liu.
Ph.D.