Journal articles: 'Dielectric waveguide'

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Krutskikh, V. V., A. Yu Sizyakova, M. S. Minkara, A. R. Ibrahim, A. E. Mirzoyan, and A. N. Ushkov. "Broadband Metal-Dielectric Waveguide Path with Low Losses in the EHF Range." Rocket-space device engineering and information systems 8, no. 3 (2021): 89–98. http://dx.doi.org/10.30894/issn2409-0239.2021.8.3.89.98.

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. The present paper is devoted to the design of a new shielded metal-dielectric waveguide with low losses (less than 0.5 dB/m) and wide bandwidth for the 90–100 GHz frequency range. Various types of waveguide structures were analyzed, such as metal waveguides, oversized metal waveguides, dielectric waveguides, dielectric waveguides with a metal shield and various designs of the dielectric filling element. Estimates of loss per unit length in them are obtained. The design of a waveguide containing an oversized round metal screen and a dielectric element consisting of a plate and a rod, located in the center of symmetry of the device, is proposed. The task of creating a transition from the investigated waveguide to a standard rectangular metal waveguide is considered. It is a horn transition from a circular cross-section to a rectangular one with a length of more than 25 wavelengths with a dielectric structure continuing the dielectric element of the waveguide path. As a result of the work, the ratios of the dimensions of the structural elements of the waveguide path and the materials used were obtained that satisfy the required losses.

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Omar, M., R. Ramzan, and O. F. Saddiqui. "Energy Tunneling Behavior in Geometrically Separated Wave Guides." Advanced Electromagnetics 6, no. 3 (October 21, 2017): 84. http://dx.doi.org/10.7716/aem.v6i3.422.

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In this paper, characteristics of energy tunneling channel between the waveguides geometrically separated by a coaxial cable are studied. The novel aspect of design is use of coaxial channel to connect the waveguides while maintaining the energy tunneling phenomena. As anticipated the tunneling frequency depends upon the length of wire inside the waveguide and the length of the coaxial cable. The tunneling frequency also depends upon the dielectric constant of the material inside the waveguide and coaxial cable. At tunneling frequency the field strength (E and H) in the channel is extremely high, making the channel extremely sensitive to small change in permittivity of dielectric occupying the channel. The advantage of the proposed design is, its ability to tune to desired tunneling frequency just by changing the length of the coaxial cable without the need to redesign the waveguide height to accommodate the long tunneling wires. This structure can be used as dielectric sensor both for solid or liquid dielectrics just by placing the sample in coaxial cable cavity, contrary to previously report work where the sample has to be placed inside the waveguide.

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Huong, Nguyen Thanh, Nguyen Van Chinh, and Chu Manh Hoang. "Wedge Surface Plasmon Polariton Waveguides Based on Wet-Bulk Micromachining." Photonics 6, no. 1 (February 27, 2019): 21. http://dx.doi.org/10.3390/photonics6010021.

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In this paper, we propose and investigate the modal characteristics of wedge surface plasmon polariton (SPP) waveguides for guiding surface plasmon waves. The wedge SPP waveguides are composed of a silver layer deposited onto the surface of a wedge-shaped silicon dielectric waveguide. The wedge-shaped silicon dielectric waveguides are explored from the anisotropic wet etching property of single crystal silicon. The wedge SPP waveguides are embedded in a dielectric medium to form the metal–dielectric interface for guiding the surface plasmon waves. The propagation characteristics of the wedge SPP waveguides at the optical telecommunication wavelength of 1.55 μm are evaluated by a numerical simulation. The influence of the physical parameters such as the dimensions of the wedge SPP waveguide and the refractive index of the dielectric medium on the propagation of the surface plasmon wave is investigated. In addition, by comparing the propagation characteristics, we derive the wedge SPP waveguide with the optimal performance.

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Wahsheh, Rami A. "Theoretical Investigation of an Air-Slot Mode-Size Matcher between Dielectric and MDM Plasmonic Waveguides." International Journal of Optics 2021 (December 14, 2021): 1–8. http://dx.doi.org/10.1155/2021/1025374.

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Hybrid integration of dielectric and plasmonic waveguides is necessary to reduce the propagation losses due to the metallic interactions and support of nanofabrication of plasmonic devices that deal with large data transfer. In this paper, we propose a direct yet efficient, very short air-slot coupler (ASC) of a length of 36 nm to increase the coupling efficiency between a silicon waveguide and a silver-air-silver plasmonic waveguide. Our numerical simulation results show that having the ASC at the interface makes the fabrication process much easier and ensures that light couples from a dielectric waveguide into and out of a plasmonic waveguide. The proposed coupler works over a broad frequency range achieving a coupling efficiency of 86% from a dielectric waveguide into a metal-dielectric-metal (MDM) plasmonic waveguide and 68% from a dielectric waveguide to an MDM plasmonic waveguide and back into another dielectric waveguide. In addition, we show that even if there are no high-precision fabrication techniques, light couples from a conventional dielectric waveguide (CDW) into an MDM plasmonic waveguide as long as there is an overlap between the CDW and ASC, which reduces the fabrication process tremendously. Our proposed coupler has an impact on the miniaturization of ultracompact nanoplasmonic devices.

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Mortazy, Ebrahim, Alireza Hassani, Francois Legare, Ke Wu, and Mohamed Chaker. "Multilayer porous waveguide for microwave low-loss applications." International Journal of Microwave and Wireless Technologies 3, no. 4 (May 18, 2011): 459–63. http://dx.doi.org/10.1017/s1759078711000596.

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A novel waveguide called multilayer porous waveguide (MPW) is proposed as microwave low-loss transmission lines. MPW is a fully rectangular dielectric waveguide composed of several periodically rectangular air gaps in a bulk dielectric that can be easily formed by placing several dielectric substrates in interval with air gaps. The loss and propagating characteristics of both TE and TM modes in MPW are studied. The TE mode confined in the air gaps has a lower loss than the TM mode spread out in air gaps and dielectric; however, the loss of TM mode is still less than that of conventional microwave waveguides. Finally, MPW is an artificial material with desirable electrical permittivity and loss that can be used in structure of conventional waveguides.

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De Boeij, Wim P., Hans S. Kanger, Gerald W. Lucassen, Cees Otto, and Jan Greve. "Waveguide CARS Spectroscopy: A New Method for Background Suppression, Using Dielectric Layers as a Model." Applied Spectroscopy 47, no. 6 (June 1993): 723–30. http://dx.doi.org/10.1366/0003702934066938.

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Waveguide Coherent Anti-Stokes Raman Spectroscopy (CARS) can be used to measure Raman-active vibrations in thin-layer dielectric waveguides. In waveguide CARS experiments, background-free spectra can be obtained when asymmetric mode combinations are applied. The degree of suppression depends on the waveguide parameters and the wavelengths used. A new method using scanning pump and Stokes beams in waveguide CARS experiments is presented, which allows the possibility of maintaining full background suppression conditions over large spectral intervals. A small controlled change in the tuning conditions results in a heterodyning of the signal with a small amount of background, thereby enhancing the small resonant signals. Several simulations for dielectric waveguides are given.

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Pochernyaev, V. N., and N. M. Syvkova. "EXTERNAL PARAMETERS OF THE CONNECTION OF A RECTANGULAR WAVEGUIDE PARTIALLY FILLED OF LINEAR DIELECTRIC WITH A RECTANGULAR WAVEGUIDE PARTIALLY FILLED OF NONLINEAR DIELECTRIC." Visnyk Universytetu “Ukraina”, no. 1 (28) 2020 (2020): 100–105. http://dx.doi.org/10.36994/2707-4110-2020-1-28-09.

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. In the article, the external parameters of the connection of a rectangular waveguide partially filled of linear dielectric with a rectangular waveguide partially filled of a nonlinear dielectric are determined. Knowledge of the external parameters of such a connection ensures the design of devices with open nonlinear elements. Promising microwave paths of radio engineering systems based on rectangular waveguides partially filled of dielectric include a wide variety of active and passive microwave devices. The plane-transverse junction of these waveguides is considered for various geometric dimensions of dielectric plates and their relative permittivity. Such a junction is characterized by reactive conductivity, which is determined through the sum of the reactive conductivities of local fields. The transverse electric field at the junction is represented through the eigenvector function of the geometric surface, which coincides with the cross section of the waveguides. The scattering matrix of the plane-transverse junction is determined through the conductivity of the sections of the two waveguides and the conductivity of the plane-transverse junction. The dependences of the traveling wave coefficient and the modulus of the reflection coefficient on the geometric dimensions of the dielectric plate are plotted taking into account the local fields generated at the plane transverse junction. At the junction of two waveguides, not only changed the geometric dimensions of the dielectric plates along the wide and narrow walls of the waveguide, but also their relative permittivity. In one case, two higher types of waves were taken into account: quasi - H30 and quasi - H12, in the other case - four higher types of waves: quasi - H30, quasi - H12, quasi - E12, quasi - H50. Calculations show that an increase in the number of higher types of waves has practically no effect on the accuracy of calculations. The results obtained indicate the rapid internal convergence of the obtained solutions and the correct choice of the transverse electric eigenvector function of rectangular waveguides partially filled of dielectric as approximate the field on the junction of two waveguides.

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Jiang, Shimin, Weiwei Li, Zhigang He, and Qika Jia. "High-Gradient Cherenkov Radiation Based on a New Dielectric-Loaded Waveguide." Particles 1, no. 1 (November 25, 2018): 279–84. http://dx.doi.org/10.3390/particles1010022.

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A new type of dielectric-loaded waveguide, the high-gradient dielectric-loaded waveguide (HG-DLW), where the Cherenkov radiation with a high gradient can be excited by relativistic electron, is proposed in this paper. Based on the simulation results, the process of the high-gradient Cherenkov radiation excited in the proposed structure is studied in details, and the amplitude of wakefields excited in proposed structure can be enhanced by over six times compared with that from ordinary dielectric-loaded waveguides.

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Morozov, V. M., V. I. Magro, and E. Yu Trakhtman. "Infinite linear waveguide antenna array with metal-dielectric structures in the "floquet channel"." Journal of Physics and Electronics 28, no. 1 (September 10, 2020): 91–96. http://dx.doi.org/10.15421/332015.

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An electrodynamics calculation is performed for an infinite waveguide antenna array in the form of open ends of waveguides, in the near zone of which a metal-dielectric structure is located. This metal-dielectric structure is located in the "Floquet channels" and is a combination of a dielectric coating over the antenna array and horns. In this case, the horns are not a continuation of the waveguides, but are located at some distance from them. The space between the waveguides and the horns is filled with a dielectric. A system of equations that allows calculating the reflection coefficients of incident waves in waveguides is obtained.

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Mayboroda, D. V., and S. O. Pogarsky. "AN ANTENNA BASED ON A HYBRID METAL–DIELECTRIC STRUCTURE." Radio physics and radio astronomy 26, no. 3 (September 14, 2021): 270–77. http://dx.doi.org/10.15407/rpra26.03.270.

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Purpose: Nowadays, in the millimeter frequency range, the dielectric waveguides of various modifications have certain advantages over the standard metal waveguides, primarily due to the possibility of creating functional units based on them. This is due to the relative simplicity and low cost of manufacturing the dielectric waveguides and functional units using them, the high degree of their integration with active elements, the use in their manufacture of different dielectrics and polymers with a wide range of material constants and a variety of mechanical properties (in particular, some materials have a significant flexibility). After making a series of physical experiments we have found the possibility of implementing the frequency selection and radiation into free space of electromagnetic waves by a hybrid metal-dielectric structure. Design/methodology/approach: The studied electrodynamic structure belongs to the class of hybrid metal-dielectric structures. It includes a modified inverted dielectric waveguide with a periodic sequence on the dielectric plate of fifteen dielectric rods with metallized coating on one of the faces placed outwards. The structure efficiency was estimated by the voltage standing-wave ratio (VSWR) values and power attenuation in the duct. The measurements were made with the reflectometer method. To estimate the degree of electromagnetic field concentration near the rod inhomogeneities in the near zone, the mobile probe method was used. The field structures were visualized with the method of isolines. Findings: The results of a series of experimental investigations showed the possibility of matching the structure with the external waveguides in the frequency range of 26.5-32.5 GHz with the voltage standing-wave ratio (VSWR) less than 1.8. The frequency dependence of attenuation is oscillatory with clearly expressed frequency ranges with small and large attenuation values. Moreover, the dependence is almost periodic, which is typical of periodic structures. The frequency response slope in the transition zones can be quite high and reach values of 41.26 dB/GHz. The degree of concentration of the electric field near the waveguide dielectric rod and the degree of excitation of the dielectric inhomogeneities was found by directly measured electric field strength in the near zone. Measurements of energy characteristics made under the short-circuit conditions for the main guide and in the mode of matched load of the main guide showed both the ability to control the polarization characteristics and the ability to change the appearance of the pattern and its orientation in space. Conclusions: It has been experimentally proven that a hybrid metal-dielectric structure, being a modified inverted dielectric waveguide with a periodic sequence on the dielectric plate of fifteen dielectric rods with metalized coating on one of the faces placed outwards, can be effectively integrated into a standard transmission line. It is found that this structure can be matched with the external circuits in a fairly wide frequency range. It is also found that in different frequency ranges this hybrid metal-dielectric structure shows the possibility of both efficient frequency selection and radiation in free space. Antenna measurements have shown the beam pattern shape controllability. Key words: inverted dielectric waveguide, periodic sequence, voltage standing-wave ratio (VSWR), attenuation, reflectometer method, mobile probe method, directivity pattern

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Ouassal, Hassna, Jafar Shaker, Langis Roy, Khelifa Hettak, and Reza Chaharmir. "Line Defect-Layered EBG Waveguides in Dielectric Substrates." International Journal of Antennas and Propagation 2018 (June 4, 2018): 1–9. http://dx.doi.org/10.1155/2018/3469730.

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A dielectric-based multilayer structure composed of U-shaped rings (ML-UR) is used to develop a class of novel electromagnetic band gap (EBG) slab waveguide. The structure has two band gaps that narrow down as dielectric constant is increased. The EBG slab waveguide is created by embedding a single-layer line defect inside the 3D crystal of the EBG slab guide. Unlike our previously published foam-based EBG structure, the use of dielectric spacer in the EBG waveguides offers significant advantages in terms of overall size, structure reliability, and design flexibility. The waveguide structures reported in this paper are designed to operate at X-band (8–12 GHz) while being fed by coplanar-slotline transitions. Prototypes were fabricated and characterized experimentally. The insertion loss decreases by decreasing the number of full lattices of ML-UR surrounding the channels. The proposed waveguide has potential in microwave components such as directional couplers, phase shifters, and antenna array feeding networks.

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Morozov, V. M., and V. I. Magro. "Investigation of waveguide antenna arrays with layered dielectrics." Journal of Physics and Electronics 27, no. 2 (December 27, 2019): 111–16. http://dx.doi.org/10.15421/331935.

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A general methodology for calculating antenna arrays with layered dielectric is considered. To demonstrate the proposed methodology, we consider the solution of the problem of radiation of linear waveguide array. Plane-parallel waveguides have a finite wall thickness. Antenna array scans in E and H planes. This problem is solved using Fredholm integral equations of the second kind. To solve the problem, the entire domain of the electromagnetic field is divided into partial intersecting regions An example of constructing Green’s functions of selected partial regions with allowance for their dielectric filling is considered. The formulation of the boundary-value problem for the antenna array in the form of Fredholm integral equations of the second kind using the technique of dividing the determination domain into partial regions with Green’s functions allows us to solve the following problem: calculations of the antenna array with dielectric plugs in the waveguides and with a dielectric coating over the antenna array. This technique allows optimization of dielectric parameters with the aim of aperture matching of the antenna array. The calculation results of the dependence of the reflection coefficient on the phase shift between waveguides in the H-plane are presented. The calculations are performed for different values of the dielectric constant of the plugs in the waveguides and the dielectric constant of the dielectric layer above the antenna array. The influence of the geometric dimensions of the plugs in the waveguides and the dielectric coating above the array is studied.

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Maeda, Hiroshi, Huili Chen, Kazuya Tomiura, and Kiyotoshi Yasumoto. "Numerical and Experimental Study on Confinement in Y-Shaped Post Wall Branching Waveguide." Mobile Information Systems 10, no. 2 (2014): 217–28. http://dx.doi.org/10.1155/2014/514825.

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Post wall waveguides consist of dielectric or metallic cylinders for microwave around 4 GHz were experimentally and numerically investigated. The structure attracts interests for application of transmission circuit for three-dimensionally integrated planar circuit in millimeter wavelength. In straight waveguide with dielectric cylinders, confinement of microwave is poor, when the post wall was composed of a pair of single row of cylinders. The confinement was improved as increase of rows of post wall. In metallic cylinders, microwave was well confined even when a pair of single row of cylinders composed the waveguide. After confirming confinement of the electromagnetic field, Y-shaped branches of post wall waveguide consisted of dielectric cylinders for microwave were similarly investigated for dielectric rods. The confinement was also improved by increase of post wall up to 3 layers. These results are applicable for fundamental design and fabrication of integrated circuit for microwave and millimeter wave.

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Yan, Min, and Min Qiu. "Compact Optical Waveguides Based on Hybrid Index and Surface-Plasmon-Polariton Guidance Mechanisms." Active and Passive Electronic Components 2007 (2007): 1–7. http://dx.doi.org/10.1155/2007/52461.

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Surface-plasmon-polariton (SPP) waveguides made of materials available in nature have, in general, been found to suffer from very high absorption loss when light confinement is beyond diffraction limit. In this paper, the possibility of combining both the conventional index-guiding and the SPP-guiding mechanisms together into one single waveguide is being explored. Such waveguides, expectedly, inherent the low-loss feature of all-dielectric waveguides as well as the superior mode field confinement possessed by SPP waveguides. By using experimentally ready materials, it is theoretically shown that compact metallodielectric waveguides can be designed with a∼500×500 nm2core size around the 1550 nm telecommunication wavelength. The examined waveguides can be interpreted as a gap SPP waveguide with an inner dielectric core. Compared to pure SPP waveguides, such hybrid waveguides have a comparable mode field size, but with significantly lower loss (∼0.05 dB/μmfor either quasi-TE or quasi-TM operation). Therefore they can be potentially deployed for a range of integrated photonic applications.

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Grigoriev, Andrey D. "NEW WAVEGUIDE METHOD FOR DIELECTRIC PARAMETER MEASUREMENT." Journal of the Russian Universities. Radioelectronics, no. 5 (December 6, 2018): 33–38. http://dx.doi.org/10.32603/1993-8985-2018-21-5-33-38.

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Perfect knowledge of dielectric parameters is necessary for its application in various devices. In spite of the whole range of measurement techniques, their practical implementation in the microwave frequency band runs into some difficulties. This article describes a new method for nonmagnetic dielectrics permittivity and loss tangent measurement in the microwave frequency band. A dielectric specimen slab is placed in the short-circuited waveguide section normal to its axis and fills the whole cross-section of the waveguide at approximately quarter wavelength from its short-circuited endpoint. By means of the vector network analyzer the waveguide section reflection factor is measured. Objective function is de-termined as difference between calculated and measured module and phase of the reflection factor. Specific code for ob-jective function calculation and its minimization is worked out. Minimization of this function by varying dielectric parameters makes it possible to find real values of these parameters. The method needs no de-embedding and can be used with non-calibrated waveguide-to-coax transitions. Also it is less sensitive to the noise component of reflected signal. The testing results show that new method’s error does not exceed 0.2 % for relative permittivity and 1% for dielectric loss tangent.

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Shaaban, Adel, Yi-Chun Du, and Lotfy Rabeh Gomaa. "Extension of an FFT-Based Beam Propagation Method to Plasmonic and Dielectric Waveguide Discontinuities and Junctions." Applied Sciences 9, no. 20 (October 16, 2019): 4362. http://dx.doi.org/10.3390/app9204362.

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We adapted a fast Fourier transform-based Beam Propagation Method (FFT-BPM) to investigate waveguide discontinuities in plasmonic waveguides. The adaptation of the FFT-BPM to treat transverse magnetic (TM) fields requires the circumvention of two major difficulties: the mixed derivatives of the magnetic field and waveguide refractive index profile in the TM wave equation and the step-like index change at the transverse metal-dielectric boundary of the plasmonic guide and the transverse boundaries of the dielectric waveguide as well. An equivalent-index method is adopted to transform TM fields to transverse electric (TE) ones, thus enabling the benefit of the full power and simplicity of the FFT-BPM. Moreover, an appropriate smoothing function is used to approximate the step-like refractive index profile in the transverse direction. At the junction plane, we used an accurate combined spatial-spectral reflection operator to calculate the reflected field. To validate our proposed scheme, we investigated the modal propagation in a silicon waveguide terminated by air (like a laser facet in two cases: with and without a coating layer). Then we considered a subwavelength plasmonic waveguide (metal-insulator-metal MIM) butt-coupled with a dielectric waveguide, where the power transmission efficiency has been calculated and compared with other numerical methods. The comparison reveals good agreement.

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Belyaev, B. A., K. V. Lemderg, and V. F. Shabanov. "Investigation of electromagnetic wave transmission line based on coupled dielectric resonators." Доклады Академии наук 489, no. 3 (November 29, 2019): 240–45. http://dx.doi.org/10.31857/s0869-56524893240-245.

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An analogue of optical waveguide consisting of metallic nanoparticles chain was investigated using modified cylindrical dielectric resonators (DR) in the microwave range. The two lowest resonances of the DR correspond to the dipole and quadrupole modes of oscillations similar to plasma oscillations in spherical nanoparticles. It is shown that a waveguide consisting of seven resonators has high frequency selective properties and relatively low losses, if the resonances of quadrupole modes are used to form its bandwidth. The characteristics of the studied waveguide remain almost unchanged at its bending by 90. Cross-section of the main part of energy localization in waveguide is 5 times less than the length of the electromagnetic wave, which roughly corresponds to the optical waveguides based on plasmon oscillations in nanoparticles.

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Krutskikh, V. V., S. M. Minkara, A. R. Ibrahim, A. E. Mirzoyan, and A. N. Ushkov. "Shielded low-loss metal-dielectric waveguide for frequency range of 90–110 GHz." Journal of «Almaz – Antey» Air and Space Defence Corporation, no. 2 (June 23, 2021): 7–14. http://dx.doi.org/10.38013/2542-0542-2021-2-7-14.

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This study is dedicated to the development of a new design of the shielded low-loss metal-dielectric waveguide for the frequency range of 90–100 GHz. High level of losses in metal is a major challenge complicating implementation of commonly used waveguides in the specified wavelength range. The study objective was to develop the proposal regarding the waveguide design with losses lower than 0.5 dB/m, with persistent wave polarisation. To address the problem, we analysed various waveguide design solutions and estimated losses per unit length along with the possibility to implement the proposed design. We proposed the final variant of waveguide design and selected parameters of structural members to solve the problem at hand.

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Divakov, Dmitriy V., Alexandre A. Egorov, Konstantin P. Lovetskiy, Leonid A. Sevastianov, and Andrey S. Drevitskiy. "Leaky waves in planar dielectric waveguide." Discrete and Continuous Models and Applied Computational Science 27, no. 4 (December 15, 2019): 325–42. http://dx.doi.org/10.22363/2658-4670-2019-27-4-325-342.

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A new analytical and numerical solution of the electrodynamic waveguide problem for leaky modes of a planar dielectric symmetric waveguide is proposed. The conditions of leaky modes, corresponding to the Gamow-Siegert model, were used as asymptotic boundary conditions. The resulting initial-boundary problem allows the separation of variables. The emerging problem of the eigen-modes of open three-layer waveguides is formulated as the Sturm-Liouville problem with the corresponding boundary and asymptotic conditions. In the case of guided and radiation modes, the Sturm-Liouville problem is self-adjoint and the corresponding eigenvalues are real quantities for dielectric media. The search for eigenvalues and eigenfunctions corresponding to the leaky modes involves a number of difficulties: the problem for leaky modes is not self-adjoint, so the eigenvalues are complex quantities. The problem of finding eigenvalues and eigenfunctions is associated with finding the complex roots of the nonlinear dispersion equation. To solve this problem, we used the method of minimizing the zero order. An analysis of the calculated distributions of the electric field strength of the first three leaky modes is given, showing the possibilities and advantages of our approach to the study of leaky modes.

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DARYANOOSH, S., and H. MEHDIAN. "Dispersion relation for azimuthal electromagnetic surface waves on a magnetized annular plasma in a metal waveguide with coaxial anisotropic dielectric inner coating." Journal of Plasma Physics 73, no. 6 (December 2007): 839–55. http://dx.doi.org/10.1017/s0022377807006356.

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AbstractThe dispersion relation of azimuthal electromagnetic surface waves on a magnetized annular plasma surrounded by a metallic cylindrical coaxial anisotropic dielectric lined waveguide is obtained. The thickness of the dielectric and its location in the waveguide are studied with respect to their effects on the number of spectra observed. The graphs of frequency spectra against the ratio of radii of the annular plasma and η = ωpe/Ωe are plotted. Finally, surface E-modes for coaxial anisotropic and isotropic dielectrics have been investigated.

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Seidel, Andreas, Jacek Gosciniak, Maria U. Gonzalez, Jan Renger, Carsten Reinhardt, Roman Kiyan, Romain Quidant, Sergey I. Bozhevolnyi, and Boris N. Chichkov. "Fiber-Coupled Surface Plasmon Polariton Excitation in Imprinted Dielectric-Loaded Waveguides." International Journal of Optics 2010 (2010): 1–6. http://dx.doi.org/10.1155/2010/897829.

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We present fiber-coupled dielectric-loaded plasmonic waveguides for 1.55 μm telecom wavelength fabricated by two-photon polymerization and nanoimprint lithography. The waveguide structures include 100-μm-long plasmonic waveguides connected on both ends to tapered dielectric waveguides used for end-fire coupling with optical fibers. The excitation of plasmonic waveguides is verified via polarization-resolved measurements of the overall transmission, demonstrating thereby that this technology is suitable in principle for the integration of plasmonic components into fiberoptics. Loss mechanisms are investigated and improvements suggested to reduce transmission losses and consequently increase the viability of practical application.

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Pevneva, N. A., A. A. Kopshai, and A. L. Gurskii. "Simulation of electromagnetic field distribution in the measuring cell for determining the dielectric permittivity of materials at microwave frequencies." Doklady BGUIR 18, no. 6 (October 1, 2020): 75–80. http://dx.doi.org/10.35596/1729-7648-2020-18-6-75-80.

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To determine the dielectric permittivity of materials in a wide frequency range with the automation of measurements and the necessary accuracy, measuring cells have been created to ensure the simplicity of the design of the waveguide path. In order to obtain information about the suitability of measuring cells based on irregular SHF waveguides for estimation of dielectric parameters of materials, we simulated the structure of electromagnetic field in the system consisting of two irregular waveguides and waveguide chamber placed between them using a three-dimensional electrodynamic simulation in Ansoft HFSS package environment. The distribution of the electric field was simulated when an empty polyethylene tube, a rod of fluoroplastic and a rod of textolite are placed in the measuring cell. It was demonstrated that high order modes fade out in irregular waveguide and do not affect the precision of obtained results, and significant edge effects were not detected. It allows one to utilize measuring cells based on irregular waveguides together with a scalar or vector network analyzer and using the partial filling of the waveguide method or the modified Nicholson – Ross – Weir method for measurements of dielectric permittivity  of materials. The results of modeling the dependence of the amplitude and phase of the reflection coefficient of the textolite and fluoroplastic on the frequency in Ansoft HFSS environment are given. The simulation results are compared with the results obtained experimentally. The frequency dependencies of  were obtained experimentally for test materials – textolite and fluoroplastic – in the frequency range of 25,95–37,50 GHz. The experimental data are in satisfactory agreement with the results of theoretical calculations and do not go beyond the boundaries specified by the measurement uncertainty.

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Doerr, Christopher R., and Herwig Kogelnik. "Dielectric Waveguide Theory." Journal of Lightwave Technology 26, no. 9 (May 2008): 1176–87. http://dx.doi.org/10.1109/jlt.2008.923632.

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Huang, Yin, Changjun Min, Liu Yang, and Georgios Veronis. "Nanoscale Plasmonic Devices Based on Metal-Dielectric-Metal Stub Resonators." International Journal of Optics 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/372048.

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We review some of the recent research activities on plasmonic devices based on metal-dielectric-metal (MDM) stub resonators for manipulating light at the nanoscale. We first introduce slow-light subwavelength plasmonic waveguides based on plasmonic analogues of periodically loaded transmission lines and electromagnetically induced transparency. In both cases, the structures consist of a MDM waveguide side-coupled to periodic arrays of MDM stub resonators. We then introduce absorption switches consisting of a MDM plasmonic waveguide side-coupled to a MDM stub resonator filled with an active material.

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Teng, Da, and Kai Wang. "Theoretical Analysis of Terahertz Dielectric–Loaded Graphene Waveguide." Nanomaterials 11, no. 1 (January 15, 2021): 210. http://dx.doi.org/10.3390/nano11010210.

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The waveguiding of terahertz surface plasmons by a GaAs strip-loaded graphene waveguide is investigated based on the effective-index method and the finite element method. Modal properties of the effective mode index, modal loss, and cut-off characteristics of higher order modes are investigated. By modulating the Fermi level, the modal properties of the fundamental mode could be adjusted. The accuracy of the effective-index method is verified by a comparison between the analytical results and numerical simulations. Besides the modal properties, the crosstalk between the adjacent waveguides, which determines the device integration density, is studied. The findings show that the effective-index method is highly valid for analyzing dielectric-loaded graphene plasmon waveguides in the terahertz region and may have potential applications in subwavelength tunable integrated photonic devices.

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Polat, Ersin, Henning Tesmer, Roland Reese, Matthias Nickel, Dongwei Wang, Peter Schumacher, Rolf Jakoby, and Holger Maune. "Reconfigurable Millimeter-Wave Components Based on Liquid Crystal Technology for Smart Applications." Crystals 10, no. 5 (April 27, 2020): 346. http://dx.doi.org/10.3390/cryst10050346.

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This paper presents recent development of tunable microwave liquid crystal (LC) components in the lower millimeter wave (mmW) regime up to the W-band. With the utilization of increasing frequency, conventional metallic waveguide structures prove to be impractical for LC-based components. In particular, the integration of the electric bias network is extremely challenging. Therefore, dielectric waveguides are a promising alternative to conventional waveguides, since electrodes can be easily integrated in the open structure of dielectric waveguides. The numerous subcategories of dielectric waveguides offer a high degree of freedom in designing smart millimeter wave components such as tunable phase shifters, filters and steerable antennas. Recent research resulted in many different realizations, which are analyzed in this paper. The first demonstrators of phased array antennas with integrated LC-based phase shifters are reviewed and compared. In addition, beam steering with a single antenna type is shown. Furthermore, the possibility to realize tunable filters using LC-filled dielectric waveguides is demonstrated.

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CUI, LUNA, GANG SONG, LI YU, PEILING LANG, and JINGHUA XIAO. "TUNABLE BAND-STOP PLASMONIC FILTER BASED ON SYMMETRICAL TOOTH-SHAPED WAVEGUIDE COUPLES." Modern Physics Letters B 27, no. 14 (May 16, 2013): 1350101. http://dx.doi.org/10.1142/s0217984913501017.

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A simple plasmonic filter with symmetrical tooth-shaped waveguides is proposed and investigated by using finite element method. It is found that the structure with a single symmetrical tooth-shaped waveguide couple can realize a tunable band-stop filter. Attributed to cascaded symmetrical tooth-shaped waveguide couples, the structure can achieve a flat band-stop response with no intensity variation over the transmission spectrum. And the central wavelength of the stopband linearly increases with the simultaneous increasing of depths of waveguides. Moreover, reduced structure size can be achieved by controlling the dielectric constant of the medium.

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Tang, Ting Ting, and Li Luo. "Refractive-Index Sensor Based on Metal-Insulator-Metal Waveguides." Applied Mechanics and Materials 742 (March 2015): 46–49. http://dx.doi.org/10.4028/www.scientific.net/amm.742.46.

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We propose a refractive sensor based on directional coupling between two metal-insulator-metal (MIM) waveguides to measure the refractive index change of the insulator, which is designed to be with a structure of metal-insulator-metal-insulator-metal (MIMIM) in which surface plasmon waves (SPW) are excited. The propagation properties are analyzed by coupled mode theory, and the expressions about the coupling coefficient, coupling length and sensitivity are derived. The sensing properties based on simulation results are also discussed. Compared with a dielectric waveguide, the total size of our sensor with MIMIM waveguide is about one tenth that with dielectric materials, while the sensitivity is improved ten times larger than the former.

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Tallant, David R., Karen L. Higgins, and Alan F. Stewart. "Application of Waveguide Raman Spectroscopy to High-Index Dielectric Films." Applied Spectroscopy 42, no. 2 (February 1988): 326–30. http://dx.doi.org/10.1366/0003702884428211.

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Waveguide Raman spectroscopy has been applied to the analysis of single-layer, refractory-oxide, thin-film coatings on fused silica. With the use of the film as a waveguide, the interaction of the laser probe beam with the film is maximized, and interference from the silica substrate is minimized. An amorphous film of Ta2O5 was found to be an excellent waveguide, yielding an intense Raman spectrum. Even though polycrystalline films of Y2O3, ZrO2, HfO2, and ThO2 were found to be poor waveguides, they still yielded Raman spectra containing useful structural information. Such Raman spectra showed that the ThO2 film was initially in an unusual structural form, which spontaneously transformed into cubic ThO2. Even for films yielding relatively weak Raman bands, substrate Raman scattering was not a serious interference. Representative spectra are presented, along with a brief discussion of the requirements for coupling optical beams into films with large refractive indices.

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Denisenko, D. V., and V. V. Radchenko. "Quasistasic modeling of edge fields in planar resonators." Issues of radio electronics 49, no. 5 (July 5, 2020): 64–70. http://dx.doi.org/10.21778/2218-5453-2020-5-64-70.

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This paper discusses quasistatic waveguide model for planar resonator placed in multilayer dielectic media, which do not use effective parameters such as effective width of resonator and effective dielectric constant. It allows to use waveguide model in new approach. Edge field is modeled by inclusion of LC-lumped element circuit where values of inductances and capacitances we determined from the solving of electrostatic Laplace equation by the method of moment using the three-dimensional Green function for multilayer dielectric media. A computational experiment showed that the proposed model is effective in modeling planar resonators of complex shape and requires low computational resources.

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Ferrari, Simone, Carsten Schuck, and Wolfram Pernice. "Waveguide-integrated superconducting nanowire single-photon detectors." Nanophotonics 7, no. 11 (September 20, 2018): 1725–58. http://dx.doi.org/10.1515/nanoph-2018-0059.

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AbstractIntegration of superconducting nanowire single-photon detectors with nanophotonic waveguides is a key technological step that enables a broad range of classical and quantum technologies on chip-scale platforms. The excellent detection efficiency, timing and noise performance of these detectors have sparked growing interest over the last decade and have found use in diverse applications. Almost 10 years after the first waveguide-coupled superconducting detectors were proposed, here, we review the performance metrics of these devices, compare both superconducting and dielectric waveguide material systems and present prominent emerging applications.

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Benimetskiy, F., A. Yulin, V. Kravtsov, A. Mikhin, I. Iorsh, A. Samusev, and D. N. Krizhanovskii. "Guided exciton-polaritons in a subwavelength dielectric slab integrated with a 2D semiconductor." Journal of Physics: Conference Series 2015, no. 1 (November 1, 2021): 012014. http://dx.doi.org/10.1088/1742-6596/2015/1/012014.

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Abstract New-generation nonlinear planar polaritonic devices based on 2D semiconductors demonstrate great potential for a wide range of practical applications. In this work, we experimentally study strong light–matter coupling between waveguide photons and excitons in a photonic system based on dielectric slab waveguides integrated with 2D transition metal dichalcogenides.

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Joozdani, M. Z. "Enhancement of transmission line model to analyze the matching section of a dielectric-loaded accelerator with sharp discontinuities." Journal of Instrumentation 17, no. 05 (May 1, 2022): P05039. http://dx.doi.org/10.1088/1748-0221/17/05/p05039.

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Abstract In this paper, a compact and single-mode X-band dielectric-loaded matching section with constant tilt angle, blended edges, and two discontinuities at both ends is analyzed by the transmission line model. This matching section is designed as a high-power injection coupler to a dielectric-loaded accelerating structure (DLA). Although the transmission line model is a powerful tool for single-mode structures, because of radial inhomogeneity and lack of single value for characteristic impedance in dielectric-loaded structures, this method is not applicable in non-uniform dielectric-loaded structures. To solve this problem, it is shown that a dielectric-loaded waveguide (DLW) can be modeled by a dielectric-filled waveguide (DFW) with the same parameters of the phase constant, power flow, and dielectric loss. The characteristic impedance of a dielectric-filled waveguide can be determined by three structural parameters of the real and imaginary parts of the dielectric material and inner radius. These structural parameters can be found by solving a non-linear equation system made by equality of the parameters of the dielectric-loaded and dielectric-filled waveguides. To analyze the matching section, it is stratified to low thickness and uniform DLWs in the propagation direction and every segment is substituted by its equal DFW model. However, because of sharp variation in dielectric region at two ends of the flared section, solving the non-linear equation system is difficult at these points due to the lack of a proper initial point for the answer. Therefore, two virtual sections are added at the discontinuities to smoothen the variation of the dielectric region. Then, the total transmission matrix and scattering matrix parameters can be obtained without considering the added virtual sections. Moreover, the matching section is simulated by a full-wave electromagnetic software and the results of the scattering matrix parameters are compared with the ones of the proposed method. It is shown that there is a good agreement between the total behavior of the simulation and analytical results and the proposed method has acceptable accuracy.

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Trubin, Alexander. "MUTUAL COUPLING COEFFICIENTS OF ROTATING RECTANGULAR DIELECTRIC RESONATORS IN CUT-OFF RECTANGULAR WAVEGUIDE." Information and Telecommunication Sciences, no. 1 (June 29, 2021): 48–54. http://dx.doi.org/10.20535/2411-2976.12021.48-54.

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Background. A further increase in the speed of information transfer is determined by more stringent requirements for the elements of communication devices. One of the most important components of such devices is various filters, which are often made on the basis of dielectric resonators. Calculation of the parameters of multi-section filters is impossible without further development of the theory of their design. The development of filter theory is based on electrodynamic modelling, which involves calculating the coupling coefficients of dielectric resonators in various transmission lines. Objective. The aim of the research is to calculate and study the coupling coefficients of rectangular dielectric resonators with a rectangular metal waveguide when their axes rotate. Investigation of new effects to improve the performance of filters and other devices based on them. Methods. Methods of technical electrodynamics are used to calculate and analyse the coupling coefficients. The end result is to obtain new analytical formulas for new structures with rectangular dielectric resonators, which make it possible to analyse and calculate their coupling coefficients. Results. New analytical expressions are found for the coupling coefficients of dielectric resonators with the rotation of their axes in a rectangular waveguide. Conclusions. The theory of designing filters based on new structures of dielectric resonators with rotation of their axes in metal waveguides has been expanded. New analytical relationships and new patterns of change in the coupling coefficients are found. Keywords: dielectric filter; rectangular dielectric resonator; rotation; coupling coefficients.

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Zhang, Yi Lei, Yong Gang Wang, and Li Yu. "Hybrid Plasmonics Waveguide Properties of Dielectric Nanowires Coupling with Metal Substrate." Advanced Materials Research 1096 (April 2015): 31–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1096.31.

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A hybrid plasmonic waveguide system consisting of a high-permittivity cylinder waveguide embedded in a low-permittivity dielectric deposited on a metal substrate is comprehensive investigated. With the strong coupling between dielectric cylindrical waveguide mode and the long-range surface plasmon polaritons (LRSPP) mode of a thin metal film, the basic waveguiding properties, including the effective mode area, the propagation length, the mode character, and the figure of merit (FoM) can be achieved. Our results may provide valuable references for waveguiding metal -supported dielectric nanowires for practical applications. An investigation of the effect of structural perturbations indicates that the disturbance of the dielectric nanowires of our proposed waveguide with different surrounding dielectric layer would have a great influence on the experiment results.

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Friel, Richard, and Dani Or. "Frequency analysis of time‐domain reflectometry (TDR) with application to dielectric spectroscopy of soil constituents." GEOPHYSICS 64, no. 3 (May 1999): 707–18. http://dx.doi.org/10.1190/1.1444580.

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Standard analyses of time‐domain reflectometry (TDR) waveforms in environmental sciences use traveltime along waveguides and reflection amplitude to infer water content and bulk electrical conductivity, respectively. TDR waveforms contain additional information on the frequency‐dependent dielectric permittivity of media, which can be extracted through transformation of TDR waveforms into the frequency domain. The primary objective of this study was to provide a more complete picture of TDR responses in the frequency domain and to improve estimation of dielectric properties. The frequency content of TDR waveforms interacting with various constituents was measured and compared with predictions based on known dielectric properties and waveguide geometries. The study highlights the dominant role of the S11 scatter function, which describes how a TDR signal is modified by media properties and probe configuration. Scatter functions derived from transformed TDR waveforms into the frequency domain were used for estimation of frequency‐dependent dielectric properties of wet soils. The main results were (1) a more complete picture of TDR waveforms in the frequency domain; (2) estimation and use of scatter functions for TDR‐based dielectric permittivity estimation; and (3) highlights of potential usefulness and limitations of a commonly used TDR cable tester (Tektronix 1502B) and waveguide design for estimation of frequency‐dependent dielectric properties of porous media.

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Sandhu, Muhammad Y., and Ian C. Hunter. "Miniaturized dielectric waveguide filters." International Journal of Electronics 103, no. 10 (February 2, 2016): 1776–87. http://dx.doi.org/10.1080/00207217.2016.1138531.

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Yeo, S. P. "Dielectric-loaded elliptical waveguide." Electronics Letters 27, no. 23 (1991): 2185. http://dx.doi.org/10.1049/el:19911352.

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Konishi, Y., K. Konno, and I. Awai. "Novel dielectric-waveguide components." IEEE Transactions on Broadcasting 34, no. 1 (March 1988): 2–8. http://dx.doi.org/10.1109/11.1406.

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Mauro, Giorgio Sebastiano, Giuseppe Torrisi, Andrea Locatelli, Alberto Bacci, Costantino De Angelis, David Mascali, and Gino Sorbello. "Numerical Simulation of a Hollow-Core Woodpile-Based Mode Launcher for Dielectric Laser Accelerators." Applied Sciences 12, no. 5 (March 3, 2022): 2609. http://dx.doi.org/10.3390/app12052609.

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Hollow core microstructures powered by infrared lasers represent a new and promising area of accelerator research, where advanced concepts of electromagnetism must be used to satisfy multiple requirements. Here, we present the design of a dielectric electromagnetic band gap (EBG) mode launcher–converter for high-power coupling in dielectric laser accelerators (DLAs). The device is based on a silicon woodpile structure, and it is composed of two perpendicularly coupled hollow-core waveguides—a transverse electric (TE)-like mode waveguide (excited from laser power) and a transverse magnetic (TM)-like mode (accelerating) waveguide—in analogy with the TE10-to-TM01 waveguide mode converters of radio frequency (RF) linear accelerators (LINACs). The structure is numerically designed and optimized, showing insertion losses (IL) <0.5 dB and efficient mode conversion in the operating bandwidth. The operating wavelength is 5 μm, corresponding to a frequency of ≈60 THz, in a spectral region where solid-state continuous-wave (CW) lasers exist and are actively developed. The presented woodpile coupler shows an interaction impedance in the order of 10 kΩ, high power handling and efficiency.

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41

Shanjio Xu, S. T. Peng, and F. K. Schwering. "Effect of transition waveguides on dielectric waveguide directional couplers." IEEE Transactions on Microwave Theory and Techniques 37, no. 4 (April 1989): 686–90. http://dx.doi.org/10.1109/22.18840.

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El Afendi, Mohamed Mounkid, Mohamed Tellache, Junwu Tao, Bilal Hadjadji, and Mouncef Benmimoune. "Dielectric characterization using FEM modeling and ANNs for coaxial waveguide with conical open ended radiation." International Journal of Microwave and Wireless Technologies 9, no. 3 (March 8, 2016): 523–34. http://dx.doi.org/10.1017/s1759078716000283.

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Since last decades, microwaves have received tremendous attention as an interesting tool for material characterization. In general, standard microwave measurement methods require cutting and polishing of samples to put it in a suitable waveguide or cavity. However, several methods have been developed in order to permit a non-destructive measurement. A well-known method is based on coaxial open-ended waveguide, which is used as a sensor for dielectric characterizations. Moreover, with the requirement of new forms, developing mathematical model for each one is not convenient. Indeed, the complex structures required in the industrial field can be perfectly designed with high-performance three-dimensional software. Many attempts have been done to solve the conversion problem by proposing different algorithms. Nevertheless, they are sensitive for complex structure that contains transition part. In this paper, we propose a dielectric measurement method based on the use of coaxial waveguide. A novel algorithm for dielectric characterization of complex structures is also presented, which is based on the joint use of artificial neuronal networks and finite element method. The proposed algorithm aims to find the dielectric characterization for complex structures. Experimental evaluations applied to solid and liquid dielectrics confirm the validation of the proposed algorithm.

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Shibayama, Jun, Junji Yamauchi, and Hisamatsu Nakano. "Analysis of Plasmonic Waveguides and Gratings Using Implicit Finite-Difference Methods." Advances in OptoElectronics 2011 (September 6, 2011): 1–6. http://dx.doi.org/10.1155/2011/287284.

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Various metal-insulator-metal- (MIM-) type plasmonic waveguides and gratings are investigated numerically. Three gratings are treated: one is formed by alternately stacking two kinds of MIM waveguides, another by periodic changes in the dielectric insulator materials of an MIM waveguide, and the other by a periodic variation of the air core width in an MIM waveguide. The dispersion property of each MIM waveguide of which the grating consists is analyzed using the implicit Yee-mesh-based beam-propagation method. It is shown that the third one has a relatively large effective index modulation of the guided mode with a simple grating structure, while maintaining a low propagation loss. Further examination is given to modifications of this grating structure. The transmission characteristics are examined using the frequency-dependent implicit locally one-dimensional FDTD method. We discuss how the modified grating structure affects the bandgap of the transmission characteristics.

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Malherbe, J. A. G. "Nonradiative dielectric waveguide with perforated dielectric strip." Electronics Letters 41, no. 4 (2005): 194. http://dx.doi.org/10.1049/el:20058005.

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Geiger, Martin, Christian Wegner, Winfried Mayer, and Christian Waldschmidt. "A Wideband Dielectric Waveguide-Based 160-GHz Radar Target Generator." Sensors 19, no. 12 (June 22, 2019): 2801. http://dx.doi.org/10.3390/s19122801.

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The increasing number of radar sensors in commercial and industrial products leads to a growing demand for system functionality tests. Conventional test procedures require expensive anechoic chambers to provide a defined test environment for radar sensors. In this paper, a compact and low cost dielectric waveguide radar target generator for level probing radars is presented. The radar target generator principle is based on a long dielectric waveguide as a one-target scenery. By manipulating the field distribution of the waveguide, a specific reflection of a radar target is generated. Two realistic scenarios for a tank level probing radar are investigated and suitable targets are designed with full wave simulations. Target distances from 13 cm to at least 9 m are realized with an extruded dielectric waveguide with dielectric losses of 2 dB/m at 160 GHz. Low loss (0.5 dB) and low reflection holders are used to fix the waveguide. Due to the dispersion of the dielectric waveguide, a detailed analysis of its impact on frequency-modulated continuous wave (FMCW) radars is given and compared to free-space propagation. The functionality of the radar target generator is verified with a 160-GHz FMCW radar prototype.

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Donchenko, A. V., G. F. Zargano, and V. V. Zemlyakov. "Hybrid Types of Waves Propagating in Double Ridged Waveguide with Piecewise-Layer Dielectric Filling." Journal of the Russian Universities. Radioelectronics, no. 2 (June 5, 2018): 60–69. http://dx.doi.org/10.32603/1993-8985-2018-21-2-60-69.

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The algorithm for calculating electrodynamic characteristics of hybrid types of waves propagating in double ridged waveguide with piecewise-layered dielectric filling is presented. The double ridged waveguide structure with dielectric plates installed between the ridges, and with dielectric sample sandwiched between the dielectric substrates is consid-ered. The calculations are carried out using the method of partial regions. The presented algorithm takes into account the electromagnetic field components singularities near the dielectric and metal edges of the waveguide. The technique for calculating the electromagnetic energy losses in the double ridged waveguide with a piecewise layered dielectric filling is provided. The classification of hybrid waves is given. The spatial structures of electromagnetic fields and their planar projections (front view, top view, side view) for the first two HEwaves and the first EH-wave are demonstrated. Cutoff fre-quencies and propagation constants of HEand EH-waves are calculated. The results obtained using the described meth-od and numerical approach are compared. Then the results are analyzed.

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ZHOU, J. Y., Q. X. LI, H. Z. WANG, Z. G. CAI, X. G. HUANG, and Z. X. YU. "APPLICATIONS OF SUBMILLIMETER WAVEGUIDE TO LASER-MODE SELECTION AND NONLINEAR OPTICS." Journal of Nonlinear Optical Physics & Materials 01, no. 01 (January 1992): 151–66. http://dx.doi.org/10.1142/s0218199192000091.

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Use of submillimeter waveguide for laser transverse mode control, four-wave parametric frequency conversion, ultrafast broadband radiation generation and optical pulse shortening are presented. This paper begins with a general introduction to the applications of submillimeter waveguide to laser physics and nonlinear optics. Transverse mode selection by using an intracavity capillary is then described. Nonlinear optical frequency conversion in gas-filled hollow dielectric and hollow metallic waveguide structures is discussed. Applications of submillimeter liquid-core fiber to stimulated scattering, ultrafast broadband radiation generation and optical pulse shortening are presented, and transient stimulated Rayleigh-Kerr scattering is proposed to explain the observations of these nonlinear optical processes. It is shown that the unique characterization of high usable pump power and high power emission of submillimeter waveguides makes the waveguide structures ideal for high-power, high-energy laser physics and nonlinear optics.

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Pevneva, N. A., D. A. Kondrashov, A. L. Gurskii, and A. V. Gusinsky. "Estimation of S-parameters and dielectric permittivity of quartz ceramics samples in millimeter waveband." Doklady BGUIR 19, no. 7 (November 25, 2021): 65–71. http://dx.doi.org/10.35596/1729-7648-2021-19-7-65-71.

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A modified Nicholson – Ross – Weir method was used to determine complex parameters and dielectric permittivity of ceramic materials in the range 78.33–118.1 GHz. The measuring equipment is a meter of complex reflection and transmission coefficients, a waveguide measuring canal with a special measuring cell, consisting of two irregular waveguides and a waveguide chamber between them, which provides insignificant influence of higher-order modes. The dependences of the amplitude and phase of the reflection and transmission coefficients on frequency were obtained experimentally for fluoroplastic and three ceramic samples in the frequency range 78.33–118.1 GHz. The obtained S-parameters are processed according to an algorithm that includes their averaging based on the Fourier transform in order to obtain the values of the dielectric permittivity. Fluoroplastic was used as a reference material with a known dielectric constant. The dielectric constant of fluoroplastic has a stable value of 2.1 in the above mentioned frequency range. The dielectric constant of sample No. 1 varies from 3.6 to 2.5 at the boundaries of the range, sample No. 2 – from 3.7 to 2.1, sample No. 3 – from 2.9 to 1.5. The experimental data are in satisfactory agreement with the literature data for other frequencies taking into account the limits set by the measurement uncertainty.

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Gómez-Correa, J. E., S. E. Balderas-Mata, A. Garza-Rivera, A. Jaimes-Nájera, J. P. Trevino, V. Coello, and And S. Chávez-Cerda. "Mathematical-Physics of propagating modes in planar waveguides." Revista Mexicana de Física E 65, no. 2 Jul-Dec (July 1, 2019): 218. http://dx.doi.org/10.31349/revmexfise.65.218.

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In this paper we present a detailed physical analysis of the formation of the propagation transverse modes in planar dielectric waveguides using a mathematical-physics approach. We demonstrate physically that, at the wavelength scale, the pure stationary mode inside planar waveguide is described by the cosine function. Meanwhile, the sine function yields a quasi-stationary periodic mode.

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Ayryan, Edik, Dmitry Divakov, Alexandre Egorov, Konstantin Lovetskiy, and Leonid Sevastianov. "Modelling Leaky Waves in Planar Dielectric Waveguides." EPJ Web of Conferences 226 (2020): 02003. http://dx.doi.org/10.1051/epjconf/202022602003.

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Experimentally observed leaky modes of a dielectric waveguide are characterised by a weak tunnelling of the light through the waveguide and its long-time propagation along the waveguide. Traditional mathematical models of leaky waveguide modes meet some contradictions resolved using additional considerations. We propose a model of leaky modes in a waveguide free from the above contradictions, akin to the quantum mechanical model of the “pseudo-stable” Gamow-Siegert states. By separating variables, from the complete problem for plane inhomogeneous waves we obtain a non-self-adjoint Sturm-Liouville problem to determine the complex coefficient of the phase delay of the studied mode. The solution of the complete wave problem determines the propagation cone for the leaky mode of the waveguide, inside which there are no contradictions. Thus, solution is in qualitative agreement with experimental data.

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Journal articles on the topic 'Dielectric waveguide'

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