Relevant bibliographies by topics / Phonon

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Phonon'

Author: Grafiati
Published: 4 June 2021
Last updated: 14 December 2024

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Journal articles on the topic "Phonon"

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Zhang, Xufeng, Chang-Ling Zou, Liang Jiang, and Hong X. Tang. "Cavity magnomechanics." Science Advances 2, no. 3 (March 2016): e1501286. http://dx.doi.org/10.1126/sciadv.1501286.

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A dielectric body couples with electromagnetic fields through radiation pressure and electrostrictive forces, which mediate phonon-photon coupling in cavity optomechanics. In a magnetic medium, according to the Korteweg-Helmholtz formula, which describes the electromagnetic force density acting on a medium, magneostrictive forces should arise and lead to phonon-magnon interaction. We report such a coupled phonon-magnon system based on ferrimagnetic spheres, which we term as cavity magnomechanics, by analogy to cavity optomechanics. Coherent phonon-magnon interactions, including electromagnetically induced transparency and absorption, are demonstrated. Because of the strong hybridization of magnon and microwave photon modes and their high tunability, our platform exhibits new features including parametric amplification of magnons and phonons, triple-resonant photon-magnon-phonon coupling, and phonon lasing. Our work demonstrates the fundamental principle of cavity magnomechanics and its application as a new information transduction platform based on coherent coupling between photons, phonons, and magnons.
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Dovlatova, Alla, and Dmitri Yerchuck. "Quantum Field Theory of Dynamics of Spectroscopic Transitions by Strong Dipole-Photon and Dipole-Phonon Coupling." ISRN Optics 2012 (December 12, 2012): 1–10. http://dx.doi.org/10.5402/2012/390749.

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Matrix-operator difference-differential equations for dynamics of spectroscopic transitions in 1D multiqubit exchange-coupled (para)magnetic and optical systems by strong dipole-photon and dipole-phonon coupling are derived within the framework of quantum field theory. It has been established that by strong dipole-photon and dipole-phonon coupling the formation of long-lived coherent system of the resonance phonons takes place, and relaxation processes acquire pure quantum character. It is determined by the appearance of coherent emission process of EM-field energy, for which the resonance phonon system is responsible. Emission process is accompanied by phonon Rabi quantum oscillation, which can be time-shared from photon quantum Rabi oscillations, accompanying coherent absorption process of EM-field energy. For the case of radio spectroscopy, it corresponds to the possibility of the simultaneous observation along with (para)magntic spin resonance, the acoustic spin resonance.
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P, Munkhbaatar. "Generation and Detection of Squeezed Phonon." Физик сэтгүүл 22, no. 449 (March 13, 2022): 7–10. http://dx.doi.org/10.22353/physics.v22i449.595.

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The variance of the time dependent atomic positions and momenta is directly mapped into the quantum uctuations of the photon number of the scattered probing light. A fully quantum de-scription of the non-linear interactions between photonic and phononic fields unveils evidences of squeezing of thermal phonons. In here a pump-probe spectroscopy was proposed to observe phonon squeezing in solids. Numerical simulation showed pump-probe response due to coherent phonon and squeezed phonon in alpha-quartz.
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Prasher, Ravi S. "Mie Scattering Theory for Phonon Transport in Particulate Media." Journal of Heat Transfer 126, no. 5 (October 1, 2004): 793–804. http://dx.doi.org/10.1115/1.1795243.

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Scattering theory for the scattering of phonons by particulate scatterers is developed in this paper. Recently the author introduced the generalized equation of phonon radiative transport (GEPRT) in particulate media, which included a phase function to account for the anisotropic scattering of phonons by particulate scatterer. Solution of the GEPRT showed that scattering cross section is different from the thermal transport cross-section. In this paper formulations for the scattering and transport cross section for horizontally shear (SH) wave phonon or transverse wave phonon without mode conversion is developed. The development of the theory of scattering and the transport cross section is exactly analogous to the Mie scattering theory for photon transport in particulate media. Results show that transport cross section is very different from the scattering cross section. The theory of phonon scattering developed in this paper will be useful for the predictive modeling of thermal conductivity of practical systems, such as nanocomposites, nano-micro-particle-laden systems, etc.
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Le Dé, Brieuc, Christian J. Eckhardt, Dante M. Kennes, and Michael A. Sentef. "Cavity engineering of Hubbard U via phonon polaritons." Journal of Physics: Materials 5, no. 2 (April 1, 2022): 024006. http://dx.doi.org/10.1088/2515-7639/ac618e.

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Abstract Pump-probe experiments have suggested the possibility to control electronic correlations by driving infrared-active (IR-active) phonons with resonant midinfrared laser pulses. In this work we study two possible microscopic nonlinear electron-phonon interactions behind these observations, namely coupling of the squared lattice displacement either to the electronic density or to the double occupancy. We investigate whether photon-phonon coupling to quantized light in an optical cavity enables similar control over electronic correlations. We first show that inside a dark cavity electronic interactions increase, ruling out the possibility that T c in superconductors can be enhanced via effectively decreased electron-electron repulsion through nonlinear electron-phonon coupling in a cavity. We further find that upon driving the cavity, electronic interactions decrease. Two different regimes emerge: (i) a strong coupling regime where the phonons show a delayed response at a time proportional to the inverse coupling strength, and (ii) an ultra-strong coupling regime where the response is immediate when driving the phonon polaritons resonantly. We further identify a distinctive feature in the electronic spectral function when electrons couple to phonon polaritons involving an IR-active phonon mode, namely the splitting of the shake-off band into three bands. This could potentially be observed by angle-resolved photoemission spectroscopy.
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Carmele, Alexander, and Stephan Reitzenstein. "Non-Markovian features in semiconductor quantum optics: quantifying the role of phonons in experiment and theory." Nanophotonics 8, no. 5 (April 23, 2019): 655–83. http://dx.doi.org/10.1515/nanoph-2018-0222.

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AbstractWe discuss phonon-induced non-Markovian and Markovian features in QD-based quantum nanooptics. We cover lineshapes in linear absorption experiments, phonon-induced incoherence in the Heitler regime, and memory correlations in two-photon coherences. To qualitatively and quantitatively understand the underlying physics, we present several theoretical models that capture the non-Markovian properties of the electron–phonon interaction accurately in different regimes. Examples are the Heisenberg equation of motion approach, the polaron master equation, and Liouville propagator techniques in the independent boson limit and beyond via the path integral method. Phenomenological modeling overestimates typically the dephasing due to the finite memory kernel of phonons and we give instructive examples of phonon-mediated coherence such as phonon-dressed anticrossings in Mollow physics, robust quantum state preparation, cavity feeding, and the stabilization of the collapse and revival phenomenon in the strong coupling limit of cavity quantum electrodynamics.
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Kuroki, Yuichiro, Minoru Osada, Ariyuki Kato, Tomoichiro Okamoto, and Masasuke Takata. "Exciton-Phonon Interaction in CuAlS2 Powders." Advanced Materials Research 11-12 (February 2006): 175–78. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.175.

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High-resolution photoluminescence (PL) measurement was carried out for copper aluminum disulfide (CuAlS2) powder at 12 K. Several sharp PL lines were observed in the range from 3.580 to 3.320 eV. The emission peaks at photon energies from 3.566 to 3.459 eV were attributed to free-exciton (FE) and bound-excitons (BE). The several weak emissions at below 3.476 eV were clarified to be phonon replicas (PR) by Raman scattering and in the viewpoint of exciton-phonon interaction. We observed the one, two and three-phonon replicas related to E(LO, TO) and B2(LO, TO) vibrational modes in chalcopyrite structure. It was suggested that the strong interaction between excitons and optical phonons took place in obtained CuAlS2 powder.
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Rivera, Nicholas, Gilles Rosolen, John D. Joannopoulos, Ido Kaminer, and Marin Soljačić. "Making two-photon processes dominate one-photon processes using mid-IR phonon polaritons." Proceedings of the National Academy of Sciences 114, no. 52 (December 12, 2017): 13607–12. http://dx.doi.org/10.1073/pnas.1713538114.

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Phonon polaritons are guided hybrid modes of photons and optical phonons that can propagate on the surface of a polar dielectric. In this work, we show that the precise combination of confinement and bandwidth offered by phonon polaritons allows for the ability to create highly efficient sources of polariton pairs in the mid-IR/terahertz frequency ranges. Specifically, these polar dielectrics can cause emitters to preferentially decay by the emission of pairs of phonon polaritons, instead of the previously dominant single-photon emission. We show that such two-photon emission processes can occur on nanosecond time scales and can be nearly 2 orders of magnitude faster than competing single-photon transitions, as opposed to being as much as 8–10 orders of magnitude slower in free space. These results are robust to the choice of polar dielectric, allowing potentially versatile implementation in a host of materials such as hexagonal boron nitride, silicon carbide, and others. Our results suggest a design strategy for quantum light sources in the mid-IR/terahertz: ones that prefer to emit a relatively broad spectrum of photon pairs, potentially allowing for new sources of both single and multiple photons.
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Hasegawa, Takayuki. "Characteristics of Coherent Optical Phonons in a Hexagonal YMnO3 Thin Film." Applied Sciences 9, no. 4 (February 18, 2019): 704. http://dx.doi.org/10.3390/app9040704.

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This paper reviews our recent study on a coherent optical phonon in a hexagonal YMnO3 thin film together with related optical studies in hexagonal RMnO3 (R = Y, Lu, Ho) compounds. Coherent phonons have been observed in RMnO3 compounds by pump-probe spectroscopy with subpicosecond laser pulses, whereas the observation of coherent optical phonons was reported only in LuMnO3. Recently, we succeeded in the observation of the coherent optical phonon in a YMnO3 thin film. The generation process of the coherent optical phonon is assigned to a displacive mechanism, which is identical to that in LuMnO3. The coherent optical phonon is observed in the temperature range from 10 K to room temperature, while the oscillation intensity strongly decreases as the temperature increases to the Néel temperature of ~70 K from a lower temperature range. It is interesting that the temperature dependence is largely different from that in LuMnO3. We describe that the result can be qualitatively explained by the property of an isostructural transition around the Néel temperature in RMnO3 compounds. In addition, we briefly discuss ultrafast incoherent responses of excited electronic states from the viewpoint of the excitation photon energy of laser pulses.
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Murphy-Armando, F., É. D. Murray, I. Savić, M. Trigo, D. A. Reis, and S. Fahy. "Electronic heat generation in semiconductors: Non-equilibrium excitation and evolution of zone-edge phonons via electron–phonon scattering in photo-excited germanium." Applied Physics Letters 122, no. 1 (January 2, 2023): 012202. http://dx.doi.org/10.1063/5.0131157.

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We investigate experimentally and using first-principles theory the generation of phonons and the relaxation of carriers on picosecond timescales across the Brillouin zone of photo-excited Ge by inter-valley electron–phonon scattering. The phonons generated are typical of those generated in semiconductor devices, contributing to the accumulation of heat within the material. We simulate the time-evolution of phonon populations, based on first-principles band structure and electron–phonon and phonon–phonon matrix elements, and compare them to data from time-resolved x-ray diffuse scattering experiments, performed at the Linac Coherent Light Source x-ray free-electron laser facility, following photo-excitation by a 50 fs near-infrared optical pulse. We show that the intensity of the non-thermal x-ray diffuse scattering signal, which is observed to grow substantially near the L-point of the Brillouin zone over 3–5 ps, is due to phonons generated by scattering of carriers between the Δ and L valleys. These phonons have low group velocities, resulting in a heat bottleneck. With the inclusion of phonon decay through 3-phonon processes, the simulations also account for other non-thermal features observed in the x-ray diffuse scattering intensity, which are due to anharmonic phonon–phonon scattering of the phonons initially generated by electron–phonon scattering.
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Dissertations / Theses on the topic "Phonon"

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Iskandar, Abdo. "Phonon Heat Transport and Photon-phonon Interaction in Nanostructures." Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0010.

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Cette thèse avait pour cadre, le contrôle du transport thermique via les phonons et leur interaction avec des photons dans des nanostructures. Le manuscrit comprend cinq chapitres. Dans le premier, nous introduisons la physique des phonons et excitations élémentaires optiques de la matière. Le deuxième chapitre fournit une description des procédés de croissance, techniques de structuration et techniques de caractérisation utilisées. Dans le troisième chapitre, nous démontrons qu’à la fois, phonons et photons peuvent être confinés et interagir dans une même nanostructure. Dans le quatrième chapitre, nous montrons expérimentalement que le spectre de phonons d'un matériau peut être modifié par des mécanismes d'hybridation entre des modes de surface introduits par une nanostructuration et les modes normaux du matériau massif. Nous montrons que la forme et la taille des nanostructures sur la surface du matériau ont des effets sur le spectre de phonons du substrat. Dans le cinquième chapitre, nous montrons qu'à basse température (inférieure à 4 K), la chaleur spécifique des nanofils est équivalente à celle d'un cristal essentiellement bidimensionnel. Encore plus étonnant à l'interface entre les nanofils et le substrat, nous avons mis en évidence une transition entre une transmission élastique spéculaire et une transmission élastique diffuse. Lorsque la température augmente on observe alors une transition entre une diffusion élastique et une diffusion inélastique. L’ensemble de ces résultats laisse entrevoir des perspectives intéressantes pour le contrôle des propriétés thermiques de matériaux massifs par nanostructuration de surface
In this dissertation, we investigate phonon heat transport and phonon interaction with optical elementary excitations in nanostructures. In the first chapter, we present an introduction to the physics of phonons and optical elementary excitations in nanostructured materials. The second chapter provides a detailed description of the samples growth and fabrication procedures and the various characterization techniques used. In the third chapter, we demonstrate that phonons and photons of different momenta can be confined and interact with each other within the same nanostructure. In the fourth chapter, we present experimental evidence on the change of the phonon spectrum and vibrational properties of a bulk material through phonon hybridization mechanisms. We demonstrate that the phonon spectrum of a bulk material can be altered by hybridization between confined phonon modes in nanostructures introduced on the surface of the material and the underlying bulk phonon modes. Shape and size of the nanostructures made on the surface of the substrate have strong effects on the phonon spectrum of the bulk material itself. In the fifth chapter, we demonstrate that at low temperatures (below 4 K) the nanowire specific heat exhibits a clear contribution from an essentially two-dimensional crystal. We also demonstrate that transitions from specular to diffusive elastic transmission and then from diffusive elastic to diffusive inelastic transmission occur at the interface between nanowires and a bulk substrate as temperature increases. Perspectives include the control of bulk material thermal properties via surface nanostructuring
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Yatsui, T., and M. Ohtsu. "Dressed Photon-phonon Technology for Ultra Flat Surface." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35264.

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A reduction of the surface roughness, Ra, is required in various applications including electronic devic-es and / or optical devices. Although chemical-mechanical polishing (CMP) has been used to flatten the sur-faces, it is generally limited to reducing Ra to about 2 Å because the polishing pad roughness is as large as 10 m, and the polishing-particle diameters in the slurry are as large as 100 nm. We therefore developed a new polishing method, dressed-photon and phonon etching (DPP etching), that uses dressed photon based on an autonomous phonon-assisted process. DPP etching does not use any polishing pad, with which we obtained ultra-flat silica surface with angstrom-scale average roughness as small as Ra of 0.1 nm. Addi-tionally, we succeeded in reduction of the Ra for the three-dimensional structures. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35264
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Fung, Tsz Cheong. "Phonon magnonics." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:a36d494d-73c5-410a-82df-abd0117884e6.

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This thesis reports on some recent results in the field of acoustics and magnonics. Chapter 1 reviews the literature on magnonics and GHz frequency transducers, and highlights the lack of understanding of the growth mechanism of magnetron sputtered ZnO thin films. A novel configuration for exciting magnetostatic spinwaves using ZnO transducers is proposed. Chapter 2 is an introduction to piezoelectricity and how it can be used to generate GHz acoustic waves. A detailed formulation of the Mason model is presented in chapter 3 for predicting the performance of ZnO transducers. In chapter 4, the fabrication protocol of ZnO transducers in the custom-built sputtering plant is discussed and the transducer characterisation techniques including X-ray and pulse echo measurement are described. In chapter 5, the characterised properties of the film are compared with modelling prediction. It is found that the piezoelectric and structural properties of the fabricated ZnO films are strongly correlated and are critically dependent on the sputtering conditions and thicknesses. Chapter 6 is dedicated to plasma characterisation of the sputtering conditions using Langmuir probe diagnostics. The making of the Langmuir probe system and its development are discussed. Chapter 7 examines the various possible growth mechanisms of the ZnO films with a view to understanding how the c-axis texture forms during sputtering. The results from the Langmuir probe diagnostics and X-ray characterization indicate the detrimental in uence of ion bombardment on the film qualities. It is deduced that the c-axis self texturing of ZnO films is driven dominantly by the 'survival of the fastest' mechanism. Chapter 8 describes the theoretical formulation of magnetostatic spin-wave modes and the mechanism for which the laterally propagating magnetostatic modes are coupled to local elastic standing waves. The experimental evidence (using time resolved spectroscopy) of the acoustic excitation of magnetostatic spin-waves in a YIG film waveguide is then presented in chapter 9; the excitation efficiencies at various magnetic field configurations and carrier frequencies are investigated. Finally, chapter 10 ends the thesis with the summary of results and outlooks.
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KOMIRENKO, SERGIY MYKHAYLOVYCH. "Phonons and phonon-related effects in prospective nanoscale semiconductor devices." NCSU, 2000. http://www.lib.ncsu.edu/theses/available/etd-20001030-145518.

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The research was devoted to the theoretical investigation of lattice vibrations in low-dimensional heterostructures and bulk materials with strong polaronic coupling. The purpose of the research has been to develop the phonon theory for technologically-important materials such as nitrides of Ga and Al as well as to locate new phonon-related effects which can be utilized in artificially-created heterostructures. The electron-phonon interaction has been considered quantum mechanically.The main findings can be summarized briefly as follows: 1. Consideration of carrier-induced renormalization of acoustic phonon spectra in quantum wires revealed the possibility for the Peierls phase transition into a state with periodic lattice distortion and charge-density waves of macroscopic period in artificially-prepared structures. The phase diagram for this transition has been determined. An analytical dispersion relation for the coupled electron-phonon excitation has been derived.2. It is found that the drift of two-dimensional electrons in quantum wells can lead to efficient amplification (generation) of sub-THz coherent confined acoustic vibrations due to the Cerenkov effect when the velocity of the drifted electrons exceeds the sound velocity in the given medium. A theory has been developed to describe the confinement of acoustic modes propagating along the high-symmetry directions in cubic quantum wells.3. A theory of confinement of optical phonon modes in wurtzite quantum wells has been developed. A formalism has been derived for calculation of electron scattering rates in optically anisotropic (uniaxial) crystals and quantum wells. 4. From the comparison of the energy losses to the lattice as function of the carrier velocity obtained in frameworks of perturbative model and path-integral Thornber-Feynman approach it is found that perturbation theory can be applied for materials with intermediate polaronic coupling such a GaN and AlN. Moreover, the theoretical possibility of unique low-field runaway transport in these materials has been demonstrated.

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Lehmann, Dietmar. "Phonon Spectroscopy and Low-Dimensional Electron Systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1138734990743-55381.

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The generation and propagation of pulses of nonequilibrium acoustic phonons and their interaction with semiconductor nanostructures are investigated. Such studies can give unique information about the properties of low-dimensional electron systems, but in order to interpret the experiments and to understand the underlying physics, a comparison with theoretical models is absolutely necessary. A central point of this work is therefore a universal theoretical approach allowing the simulation and the analysis of phonon spectroscopy measurements on low-dimensional semiconductor structures. The model takes into account the characteristic properties of the considered systems. These properties are the elastic anisotropy of the substrate material leading to focusing effects and highly anisotropic phonon propagation, the anisotropic nature of the different electron-phonon coupling mechanisms, which depend manifestly on phonon wavevector direction and polarization vector, and the sensitivity to the confinement parameters of the low-dimensional electron systems. We show that screening of the electron-phonon interaction can have a much stronger influence on the results of angle-resolved phonon spectroscopy than expected from transport measurements. Since we compare theoretical simulations with real experiments, the geometrical arrangement and the spatial extension of phonon source and detector are also included in the approach enabling a quantitative analysis of the data this way. To illustrate the influence of acoustic anisotropy and carrier confinement on the results of phonon spectroscopy in detail we analyse two different applications. In the first case the low-dimensional electron system acts as the phonon detector and the phonon induced drag current is measured. Our theoretical model enables us to calculate the electric current induced in low-dimensional electron systems by pulses of (ballistic) nonequilibrium phonons. The theoretical drag patterns reproduce the main features of the experimental images very well. The sensitivity of the results to variations of the confining potential of quasi-2D and quasi-1D electrons is demonstrated. This provides the opportunity to use phonon-drag imaging as unique experimental tool for determining the confinement lengths of low-dimensional electron systems. By comparing the experimental and theoretical images it is also possible to estimate the relative strength of the different electron-phonon coupling mechanisms.In the second application the low-dimensional electron system acts as the phonon pulse source and the angle and mode dependence of the acoustic phonon emission by hot 2D electrons is investigated. The results exhibit strong variations in the phonon signal as a function of the detector position and depend markedly on the coupling mechanism, the phonon polarization and the electron confinement width. We demonstrate that the ratio of the strengths of the emitted longitudinal (LA) and transverse (TA) acoustic phonon modes is predicted correctly only by a theoretical model that properly includes the effects of acoustic anisotropy on the electron-phonon matrix elements, the screening, and the form of the confining potential. A simple adoption of widely used theoretical assumptions, like the isotropic approximation for the phonons in the electron-phonon matrix elements or the use of simple variational envelope wavefunctions for the carrier confinement, can corrupt or even falsify theoretical predictions.We explain the `mystery of the missing longitudinal mode' in heat-pulse experiments with hot 2D electrons in GaAs/AlGaAs heterojunctions. We demonstrate that screening prevents a strong peak in the phonon emission of deformation potential coupled LA phonons in a direction nearly normal to the 2D electron system and that deformation potential coupled TA phonons give a significant contribution to the phonon signal in certain emission directions
Die vorliegende Arbeit beschäftigt sich mit der Ausbreitung von akustischen Nichtgleichgewichtsphononen und deren Wechselwirkung mit Halbleiter-Nanostrukturen. Güte und Effizienz moderner Halbleiter-Bauelemente hängen wesentlich vom Verständnis der Wechselwirkung akustischer Phononen mit niederdimensionalen Elektronensystemen ab. Traditionelle Untersuchungsmethoden, wie die Messung der elektrischen Leitfähigkeit oder der Thermospannung, erlauben nur eingeschränkte Aussagen. Sie mitteln über die beteiligten Phononenmoden und eine Trennung der einzelnen Wechselwirkungsmechanismen ist nur näherungsweise möglich ist. Demgegenüber erlaubt die in der Arbeit diskutierte Methode der winkel- und zeitaufgelösten Phononen-Spektroskopie ein direktes Studium des Beitrags einzelner Phononenmoden, d.h. in Abhängigkeit von Wellenzahlvektor und Polarisation der Phononen. Im Mittelpunkt der Arbeit steht die Fragestellung, wie akustische Anisotropie und Ladungsträger-Confinement die Ergebnisse der winkel- und zeitaufgelösten Phononen-Spektroskopie beeinflussen und prägen. Dazu wird ein umfassendes theoretisches Modell zur Simulation von Phononen-Spektroskopie-Experimenten an niederdimensionalen Halbleitersystemen vorgestellt. Dieses erlaubt sowohl ein qualitatives Verständnis der ablaufenden physikalischen Prozesse als auch eine quantitative Analyse der Messergebnisse. Die Vorteile gegenüber anderen Modellen und Rechnungen liegen dabei in dem konsequenten Einbeziehen der akustischen Anisotropie, nicht nur für die Ausbreitung der Phononen, sondern auch für die Matrixelemente der Wechselwirkung, sowie eine saubere Behandlung des Confinements der Elektronen in den niederdimensionalen Systemen. Dabei werden die Grenzen weit verbreiteter Näherungsansätze für die Elektron-Phonon-Matrixelemente und das Elektronen-Confinement deutlich aufgezeigt. Für den quantitativen Vergleich mit realen Experimenten werden aber auch solche Größen, wie die endliche räumliche Ausdehnung von Phononenquelle und Detektor, die Streuung der Phononen an Verunreinigungen oder die Abschirmung der Elektron-Phonon-Kopplung durch die Elektron-Elektron-Wechselwirkung berücksichtigt.Im zweiten Teil der Arbeit wird der theoretische Apparat auf typische experimentelle Fragestellungen angewandt. Im Falle der Phonon-Drag-Experimente an GaAs/AlGaAs Heterostrukturen wird der durch akustische Nichtgleichgewichtsphononen in zwei- und eindimensionalen Elektronensystemen induzierte elektrische Strom (Phonon-Drag-Strom) als Funktion des Ortes der Phononenquelle bestimmt. Das in der Arbeit hergeleitete theoretische Modell kann die experimentellen Resultate für die Winkelabhängigkeit des Drag-Stromes sowohl für Messungen mit und ohne Magnetfeld qualitativ gut beschreiben. Außerdem wird der Einfluss unterschiedlicher Confinementmodelle und unterschiedlicher Wechselwirkungsmechanismen studiert. Dadurch ist es möglich, aus Phonon-Drag-Messungen Rückschlüsse auf die elektronischen und strukturellen Eigenschaften der niederdimensionalen Elektronensysteme zu ziehen (Fermivektor, effektive Masse, Elektron-Phonon-Kopplungskonstanten, Form des Confinementpotentials). Als weiteres Anwendungsbeispiel wird das Problem der Energierelaxation (aufgeheizter)zweidimensionaler Elektronensysteme in GaAs Heterostrukturen und Quantentrögen untersucht. Für Elektronentemperaturen unterhalb 50 K werden die Gesamtemissionsrate als Funktion der Temperatur und die winkelaufgelöste Emissionsrate (als Funktion der Detektorposition) berechnet. Für beide Größen wird erstmals eine gute Übereinstimmung zwischen Theorie und Experiment gefunden. Es zeigt sich, dass akustische Anisotropie und Abschirmungseffekte zu überraschenden neuen Ergebnissen führen können. Ein Beispiel dafür ist der unerwartet große Beitrag der mittels Deformationspotential-Wechselwirkung emittierten transversalen akustischen Phononen, der bei einer Emission der Phononen näherungsweise senkrecht zum zweidimensionalen System beobachtet werden kann
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Chamberlain, Martyn Paul. "Electrons, phonons, coupled phonon-plasmons and their interactions in semiconductor heterostructures." Thesis, University of Essex, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254491.

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Moreira, Leandro Malard. "Raman spectroscopy of graphene:: probing phonons, electrons and electron-phonon interactions." Universidade Federal de Minas Gerais, 2009. http://hdl.handle.net/1843/ESCZ-7ZFGDY.

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Since the identification of mono and few graphene layers in a substrate in 2004, intensive work has been devoted to characterize this new material. In particular, Raman spectroscopy played an important role in unraveling the properties of graphene systems. Moreover resonant Raman scattering (RRS) in graphene systems was shown to be an important tool to probe phonons, electrons and electronphononinteractions. In this thesis, by using different laser excitation energies, we obtain important electronic and vibrational properties of mono- and bi-layer graphene. For monolayer graphene, we determine the phonon dispersion near the Dirac point for the in-plane transverse optical (iTO) mode and the in-plane longitudinal acoustic (iLA) mode. These results are compared with recent theoretical calculations for the phonon dispersion around the K point. For bilayer graphene we obtain the Slonczewski-Weiss-McClure band parameters. These results show that bilayer graphene has a strong electron-hole asymmetry, which is larger than in graphite. In a gating experiment, we observe that the change in Fermi level of bilayer graphene gives rise to a symmetry breaking, allowing the observation of both the symmetric (S) and anti- symmetric (AS) phonon modes. The dependence of the energy and damping of these phonons modes on the Fermi level position is explained in terms of distinct couplings of the S and AS phonons with intraand inter-band electron-hole transitions. Our experimental results confirm the theoretical predictions for the electron-phonon interactions in bilayer graphene. We also study the symmetry properties of electrons and phonons in graphene systems as a function of the number of layers, by a group theory approach. We derive the selection rules for the electron-radiation and for the electron-phonon interactions at all points in the Brillouin zone. By considering these selection rules, we address the double resonance Raman scattering process. The selection rules for monolayer and bilayer graphene in the presence of an applied electric field perpendicular to the sample plane are also discussed.
Desde a identificação de uma ou poucas camadas de grafeno em um substrato em 2004, trabalhos intensivos tem sido feitos para se caracterizar esse novo material. Em particular, a Espectroscopia Raman Ressonante tem sido muito importante para elucidar propriedades físicas e químicas em sistemas de grafeno. A Espectroscopia Raman Ressonante também tem se mostrado como uma ferramenta importante para se estudar fônons, elétrons e interações elétron-fônon em grafeno. Nesta tese, ao usarmos diferentes energias de laser de excitação, nós obtivemos propriedades importantes sobre as estruturas eletrônicas e vibracionais para uma e duas camadas de grafeno. Para uma monocamada de grafeno, nós determinamos a dispersão de fônons perto do ponto de Dirac para o modo óptico transversal no plano (iTO) e para o modo acústico longitudinal no plano (iLA). Comparamos nossos resultados experimentais como cálculos teóricos recentes para a dispersao de fônons nas proximidades do ponto K. Para a bicamada de grafeno, nós obtivemos os parâmetros de estrutura eletrônica do modelo de Slonczewski-Weiss-McClure. Nossos resultados mostram que a bicamada de grafeno possue uma forte assimetria elétron-buraco, que por sua vez é mais forte que no grafite. Em experimentos aplicando uma tensão de porta, variamos o nível de Fermi em uma bicamada de grafeno, o que levou uma quebra de simetria, deixando assim ambos os modos de vibração simétricos (S) e anti-simétricos (AS) ativos em Raman. A dependência da energia e do amortecimento desses modos de fônons com a energia de Fermi é explicada através do acoplamento elétron-buraco intra- ou inter- banca. Nossos resultados experimentais deram suporte às previsões teóricas para interações elétron-fónon em uma bicamada de grafeno.
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Persson, Jacob. "Magnon-Phonon Coupling." Thesis, Uppsala universitet, Materialteori, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-377297.

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Recent experimental and theoretical studies have found evidence of coupled interactions between magnons and phonons. The aim of this study is to construct a model of coupled magnons and phonons, as well as analysing their frequency spectrum. The model is derived by quantizing spin and lattice degrees of freedom, and the frequency spectrum is derived by solving the equations of motion. We found that both the strength and the composition of the coupled interactions affect the frequencies of magnons and phonons, with emphasis on the magnons. Their frequencies are imaginary close to the center of the Brillouin zone, which opens questions for future research.
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Levard, Hugo. "Ingénierie phononique pour les cellules solaires à porteurs chauds." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066013/document.

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Cette thèse traite des problématiques fondamentales liées aux phonons dans le cadre des cellules solaires à porteurs chauds. Ce concept appartient aux technologies photo-voltaïques dites de troisième génération, et vise à l’extraction des porteurs de chargesphotogénérés non-encore à l’équilibre thermique avec le réseau cristallin, conduisant àun rendement théorique maximum de l’ordre de la limite thermodynamique. Un des enjeuxmajeurs est ainsi le ralentissement du refroidissement des porteurs, refroidissement qui setraduit principalement par l’émission de phonon LO via l’interactions électron-phonon.En plus de l’idée d’écranter ce dernier processus, une approche consiste à concevoir unmatériau absorbeur dans lequel le phonon LO présente un temps de vie intrinsèque pluslong qu’il ne l’est dans les matériaux classiques, favorisant ainsi sa réabsorption par lesporteurs. Dans une première partie, et utilisant la théorie de la fonctionnelle densité per-turbée, la décoposition du phonon LO est étudiée en terme d'états finaux disponibles. Suit une discussion sur le calcul du temps de vie de ces phonons, et sur la possibilité d’atteindre les critères phononiques définis comme suffisants. Dans une deuxième partie, une étude de l’interaction électron-phonon est menée dans les super-réseaux. La constante de couplage est reliée au champ électriquemacroscopique induit par le phonon LO, de sorte à pourvoir précisément rendre compte deson anisotropie. Il apparaît que la dimensionalité des populations électroniques et phononiques est différemment affectée. Cette étude appelle à développer l’analyse de ce type de structure dans le cadre des cellules à porteurs chauds
This thesis deals with fundamental issues related to phonons in hot-carrier solar cells, athird generation photovoltaic technology. This concept aims at extracting photogeneratedcharge carriers before their reach a thermal equilibrium with the lattice, and exhibits a the-oretical efficiency close to thermodynamic limit. One of the main issue is to hinder carriercooling, which occurs through LO-phonon emission. In addition to the idea of screeningthe electron-phonon interaction, one approach consists in designing an absorber in which theLO-phonon has an intrinsic lifetime longer than what it is in conventional materials, en-hancing the rate of its reabsorption by the carriers. The LO-phonon decay and lifetimeis first investigated in semiconductors within density functional perturbation theory. Spe-cific criteria for relevant absorbing materials choosing, from a phonon point of view, arederived. A full study of the LO-phonon lifetime is performed on a singular material, andthe possibility to achieve the sufficient phononic requierements is discussed. Secondly, theabove-mentioned electron-phonon interaction is modelled in superlattices. The couplingstrength is related to the LO-phonon induced macroscopic electric field, which allows tostudy the directional dependence of the phonon emission. The latter reveals to differentlyaffect the dimensionality of the electronic and phononic interacting populations. Thisstudy calls for development of these structure in the framewok of hot-carrier solar cells
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Wu, Yunhui. "Experimental Investigation of Size Effects on Surface Phonon Polaritons and Phonon Transport." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC012/document.

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La conduction thermique devient moins efficace à mesure que la taille des struc-tures diminuent en desous du micron, car la diffusion de surface des phononsdevient prédominante et limite plus efficacement les phonons que la diffusionphonon-phonon Umklapp. Des études récentes ont indiqué que les phonon po-laritons de surface (SPhPs), qui sont les ondes électromagnétiques évanescentesgénérées par l’hybridation des phonons optiques et des photons et se propageantà la surface d’une surface diélectrique polaire, pourraient servir de nouveauxvecteurs de chaleur pour améliorer les performances thermiques dans des dis-positifs micro- et nano-métriques. Nous étudions l’état des SPhPs existantdans un film submicronique diélectrique dans une large gamme de fréquences.Le calcul de la conductivité thermique des SPhPs basé sur l’équation de trans-port de Boltzmann (BTE) montre que le flux de chaleur transporté par lesSPhPs est supérieur à celui des phonons. Nous effectuons également une mesurede réflectance thermique dans le domaine temporel (TDTR) de films submi-croniques deSiNet démontrons que la conductivité thermique due aux SPhPsà haute température augmente lorsque l’épaisseur du film dimine. Les résultatsprésentés dans cette thèse ont des applications potentielles dans le domaine dutransfert de chaleur, de la gestion thermique, du rayonnement en champ proche et de la polaritoniques
Thermal conduction becomes less efficient as structures scale down into submicron sizes since phonon-boundary scattering becomes predominant and impede phonons more efficiently than Umklapp scattering. Recent studies indicated that the surface phonon polaritons (SPhPs), which are the evanescent electromagnetic waves generated by the hybridation of the optical phonons and the photons and propagating at the surface of a polar dielectric material surface, potentially serve as novel heat carriers to enhance the thermal performance in micro- and nanoscale devices. We study the condition of SPhPs existing in a dielectric submicron film with a broad frequency range. The calculaton of SPhPs thermal conductivity based on Boltzmann transport equation (BTE) demonstrates that the heat flux carried by SPhPs exceeds the one carried by phonons. We also conduct a time-domain-thermal-reflectance (TDTR) measurement of $SiN$ submicron films and demonstrate that the thermal conductivity due to the SPhPs at high temperatures increases by decreasing the film thickness. The results presented in this thesis have potential applications in the field of heat transfer, thermal management, near-field radiation and polaritonics
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Books on the topic "Phonon"

1

Sild, Olev, and Kristjan Haller, eds. Zero-Phonon Lines. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73638-4.

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Bron, Walter E., ed. Nonequilibrium Phonon Dynamics. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2501-7.

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E, Bron Walter, and North Atlantic Treaty Organization. Scientific Affairs Division., eds. Nonequilibrium phonon dynamics. New York: Plenum Press, 1985.

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E, Bron Walter, and NATO Scientific Affairs Division, eds. Nonequilibrium phonon dynamics. New York: Plenum published in cooperation with NATO Scientific Affairs Division, 1985.

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Nicholas, R. J. The magnetophonon effect. Oxford, England: Pergamon Press, 1985.

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Sun, Chang Q. Electron and Phonon Spectrometrics. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-3176-7.

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Gurevich, V. L. Transport in phonon systems. Amsterdam: North-Holland, 1986.

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Shindé, Subhash L., and Gyaneshwar P. Srivastava, eds. Length-Scale Dependent Phonon Interactions. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4614-8651-0.

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Kress, W. Phonon dispersion curves, one-phonon densities of states and impurity vibrations of metallic systems. Karlsruhe: Fachinformationszentrum Karlsruhe, 1987.

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Meissner, Michael, and Robert O. Pohl, eds. Phonon Scattering in Condensed Matter VII. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-84888-9.

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Book chapters on the topic "Phonon"

1

Böer, Karl W., and Udo W. Pohl. "Photon-Phonon Interaction." In Semiconductor Physics, 1–36. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-06540-3_11-1.

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Böer, Karl W., and Udo W. Pohl. "Photon–Phonon Interaction." In Semiconductor Physics, 1–36. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-06540-3_11-2.

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Böer, Karl W., and Udo W. Pohl. "Photon–Phonon Interaction." In Semiconductor Physics, 1–36. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-06540-3_11-3.

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Böer, Karl W., and Udo W. Pohl. "Photon–Phonon Interaction." In Semiconductor Physics, 389–424. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-69150-3_11.

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Böer, Karl W. "Photon-Phonon Interaction." In Survey of Semiconductor Physics, 280–302. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4615-9744-5_11.

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Böer, Karl W., and Udo W. Pohl. "Photon–Phonon Interaction." In Semiconductor Physics, 1–38. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-319-06540-3_11-4.

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Böer, Karl W., and Udo W. Pohl. "Photon–Phonon Interaction." In Semiconductor Physics, 429–66. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-18286-0_11.

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Weik, Martin H. "phonon." In Computer Science and Communications Dictionary, 1265. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_13959.

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Sudhir, Vivishek. "Photon-Phonon Coupling: Cavity Optomechanics." In Springer Theses, 83–101. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-69431-3_4.

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Dugaev, Vitalii K., and Vladimir I. Litvinov. "Phonons and Electron–Phonon Interaction." In Modern Semiconductor Physics and Device Applications, 101–32. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9780429285929-6.

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Conference papers on the topic "Phonon"

1

Kim, Dasom, Jin Hou, Geon Lee, Ayush Agrawal, Sunghwan Kim, Hao Zhang, Di Bao, et al. "Nanoslot-Induced Ultrastrong Phonon-Photon and Phonon-Phonon Coupling in Hybrid Organic-Inorganic Perovskites." In 2024 Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 1–2. IEEE, 2024. http://dx.doi.org/10.1109/cleo-pr60912.2024.10676597.

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Bergman, Leah, Mitra Dutta, Ki Wook Kim, Paul G. Klemens, Sergiy M. Komirenko, and Michael A. Stroscio. "Phonons, electron-phonon interactions, and phonon-phonon interactions in III-V nitrides." In Symposium on Integrated Optoelectronics, edited by Kong-Thon F. Tsen and Jin-Joo Song. SPIE, 2000. http://dx.doi.org/10.1117/12.381450.

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Abo, Shilan, Grzegorz Chimczak, Ravindra Chhajlany, Anna Kowalewska-Kudlaszyk, and Adam Miranowicz. "Hybrid photon-phonon blockade." In Quantum Technologies 2022, edited by Sara Ducci, Eleni Diamanti, Nicolas Treps, and Shannon Whitlock. SPIE, 2022. http://dx.doi.org/10.1117/12.2622111.

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Hopkins, Patrick E., John C. Duda, and Pamela M. Norris. "Contributions of Anharmonic Phonon Interactions to Thermal Boundary Conductance." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44135.

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Continued reduction of characteristic dimensions in nanosystems has given rise to increasing importance of material interfaces on the overall system performance. With regard to thermal transport, this increases the need for a better fundamental understanding of the processes affecting interfacial thermal transport, as characterized by the thermal boundary conductance. When thermal boundary conductance is driven by phononic scattering events, accurate predictions of interfacial transport must account for anharmonic phononic coupling as this affects the thermal transmission. In this paper, a new model for phononic thermal boundary conductance is developed that takes into account anharonic coupling, or inelastic scattering events, at the interface between two materials. Previous models for thermal boundary conductance are first reviewed, including the Diffuse Mismatch Model, which only consdiers elastic phonon scattering events, and earlier attempts to account for inelastic phonon scattering, namely, the Maximum Transmission Model and the Higher Harmonic Inelastic model. A new model is derived, the Anharmonic Inelastic Model, which provides a more physical consideration of the effects of inelastic scattering on thermal boundary conductance. This is accomplished by considering specific ranges of phonon frequency interactions and phonon number density conservation. Thus, this model considers the contributions of anharmonic, inelastically scattered phonons to thermal boundary conductance. This new Anharmonic Inelastic Model shows excellent agreement between model predictions and experimental data at the Pb/diamond interface due to its ability to account for the temperature dependent changing phonon population in diamond, which can couple anharmonically with multiple phonons in Pb.
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Gu, Yunfeng, Zhonghua Ni, Minhua Chen, Kedong Bi, and Yunfei Chen. "The Phonon Thermal Conductivity of a Single-Layer Graphene From Complete Phonon Dispersion Relations." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-39645.

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In this paper, the phonon scattering mechanisms of a single layer graphene are investigated based on the complete phonon dispersion relations. According to the selection rules that a phonon scattering process should obey the energy and momentum conservation conditions, the relaxation rates of combing and splitting Umklapp processes can be calculated by integrating the intersection lines between different phonon mode surfaces in the phonon dispersion relation space. The dependence of the relaxation rates on the wave vector directions is presented with a three dimensional surfaces over the first Brillion zone. It is found that the reason for the optical phonons contributing a little to heat transfer is attributed to the strong Umklapp processes but not to their low group velocities. The combing Umklapp scattering processes involved by the optical phonons mainly decrease the acoustic phonon thermal conductivity, while the splitting Umklapp scattering processes of the optical phonons mainly restrict heat conduction by the optical phonons themselves. Neglecting the splitting processes, the optical phonons can contribute more energy than that carried by the acoustic phonons. Based on the calculated phonon relaxation time, the thermal conductivities contributed from different mode phonons can be evaluated. At low temperatures, both longitudinal and in-plane transverse acoustic phonon thermal conductivities have T2 temperature dependence, and the out-of-plane transverse acoustic phonon thermal conductivity is proportion to T3/2. At room temperature, the calculated thermal conductivity is on the order of a few thousands W/m.K depending on the sample size and the edge roughness, which is in agreement with the recently measured data.
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Nomura, Masahiro. "Thermal transport by surface phonon polaritons in SiN nanofilms." In JSAP-Optica Joint Symposia. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/jsapo.2023.19p_a602_9.

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Thermal conduction becomes less efficient as structures scale down into submicron sizes due to the predominant phonon-boundary scattering that hinders phonons more efficiently than Umklapp scattering. Recent studies indicated that this thermal performance reduction could be avoided by using surface phonon-polaritons (SPhPs), which are evanescent electromagnetic waves generated by the hybridization of optical phonons and photons. These waves propagate along the surface of polar dielectric materials and could be heat carriers capable of remarkably enhancing the thermal performance of micro- and nanoscale devices. We experimentally observe the dominant heat contribution of SPhPs in SiN nanofilms
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Prasher, Ravi S. "Scattering of Phonons by Nano and Micro Particles." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-59347.

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Scattering theory for the scattering of phonons by particulate scatterers is developed in this paper. Recently the author introduced the generalized equation of phonon radiative transport (GEPRT) in particulate media which included a phase function to account for the anisotropic scattering of phonons by particulate scatterer. Solution of the GEPRT showed that scattering cross section is different than the thermal transport cross section. In this paper formulations for the scattering and transport cross section for horizontally shear (SH) wave phonon or transverse wave phonon without mode conversion is developed. The development of the theory of scattering and the transport cross section is exactly analogous to the Mie scattering theory for photon transport in particulate media. Results show that transport cross section is very different than the scattering cross section. It is also shown that for SH (horizontally shear) phonons the scattering and transport cross sections are proportional to ω8 rather than the well accepted value of ω4 in the Rayleigh regime where ω is the frequency of the SH phonons. The theory of phonon scattering developed in this paper will be useful for the predictive modeling of thermal conductivity of practical systems such as nano composites, nano-micro particle laden systems and etc.
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Stiller, Birgit, Moritz Merklein, and Benjamin J. Eggleton. "Short-scale photon-phonon interactions." In Conference on Lasers and Electro-Optics/Pacific Rim. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/cleopr.2018.th3b.1.

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Demos, S. G., J. M. Buchert, and R. R. Alfano. "Nonequilibrium phonon dynamics in forsterite." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.wk2.

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Phonon dynamics in photoexcited Forsterite–a new tunable solid state laser–has been studied by time resolved spontaneous Raman scattering following absorption in 3T2 electronic state. High rate of photoexcitation by 400 fs pulses are responsible for creation of nonequilibrium phonon population in the excited state. Phonons are generated by relaxation of the photoexcited electrons in the excited state. The finite relaxation time of phonons and strength of electron-phonon interactions produces the observed high nonequilibrium distribution during the short time after excitation. The short pulse measures the hot phonons while the longer pulses measure overall phonon population. These measurements give direct information on which nonradiative process and which phonons are involved in the relaxation of photoexcited ions in electronic state. For shortest pulse of 400 fs the 220-cm–1 mode appears to be coupled with photoexcited tetravalent chromium Cr4+ showing the nonequilibrium distribution.
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Roberts, N. A., and D. G. Walker. "Phonon Transport in Asymmetric Sawtooth Nanowires." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44341.

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Thermal transport in asymmetric sawtooth nanowires was investigated. The boundaries reflect phonons differently depending on the frequency and momentum of the phonon. These systems show thermally rectifying behavior when the boundary reflections are a function of both the direction the phonon is traveling and the frequency of the phonon. This rectifying effect could be useful for thermal management applications at all size scales, but would have to be built up from the nanoscale because of a strong dependence on the device aspect ratio and the Knudsen number of the system. Monte Carlo simulations show an accumulation of phonons at the boundary which emits phonons in a perceived rough direction where those phonons have some probability of diffuse reflections at the boundary while phonons emitted in the smooth direction only experience specular reflections at the boundary and are eventually thermalized at the opposite boundary. In this study the level of rectification of the system was linearly dependent on the device aspect ratio as long as the length of the device was near or below the phonon mean free path of the phonons.
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Reports on the topic "Phonon"

1

Kim Bongsang, Patrick Edward Hopkins, Zayd C. Leseman, Drew F. Goettler, Mehmet F. Su, Ihab Fathy El-Kady, Charles M. Reinke, and Roy H. ,. III Olsson. Phonon manipulation with phononic crystals. Office of Scientific and Technical Information (OSTI), January 2012. http://dx.doi.org/10.2172/1039017.

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Aubry, Sylvie, Thomas Aquinas Friedmann, John Patrick Sullivan, Diane Elaine Peebles, David H. Hurley, Subhash L. Shinde, Edward Stanley Piekos, and John Allen Emerson. Phonon engineering for nanostructures. Office of Scientific and Technical Information (OSTI), January 2010. http://dx.doi.org/10.2172/984139.

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Bron, W. E. Study of Transient Phonon Dynamics. Fort Belvoir, VA: Defense Technical Information Center, August 1986. http://dx.doi.org/10.21236/ada172691.

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Arnoldus, Henk F., and Thomas F. George. Laser-Linewidth Effects on the Photon-Phonon Conversion Rate at a Gas-Solid Interface,. Fort Belvoir, VA: Defense Technical Information Center, July 1986. http://dx.doi.org/10.21236/ada171469.

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Egami, T., Y. Petrov, R. J. McQueeney, G. Shirane, and Y. Endoh. Low temperature phonon anomalies in cuprates. Office of Scientific and Technical Information (OSTI), August 1998. http://dx.doi.org/10.2172/639789.

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Wolfer, W. G. Phonon Drag Dislocations at High Pressures. Office of Scientific and Technical Information (OSTI), October 1999. http://dx.doi.org/10.2172/793838.

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Evans, Paul G., Kyle M. McElhinny, and Gokul Gopalakarishnan. Scattering Tools for Nanostructure Phonon Engineering. Fort Belvoir, VA: Defense Technical Information Center, September 2013. http://dx.doi.org/10.21236/ada590229.

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Mohseni, Hooman. Phonon Avoided and Scalable Cascade Lasers (PASCAL). Fort Belvoir, VA: Defense Technical Information Center, November 2008. http://dx.doi.org/10.21236/ada498465.

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Baowen, Li. Managing Phonon Transport by Core/Shell Nanowires. Fort Belvoir, VA: Defense Technical Information Center, November 2012. http://dx.doi.org/10.21236/ada570448.

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Plummer, Ward E. Enhanced Electron-Phonon Coupling at Metal Surfaces. Office of Scientific and Technical Information (OSTI), August 2010. http://dx.doi.org/10.2172/1073629.

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