Anderson Localization of Thermal Phonons

Anderson Localization of Thermal Phonons
Author :
Publisher :
Total Pages : 161
Release :
ISBN-10 : OCLC:1004377162
ISBN-13 :
Rating : 4/5 (62 Downloads)

Synopsis Anderson Localization of Thermal Phonons by : Jonathan Michael Mendoza

In semiconductor devices, thermal energy is carried by phonons, the quantized excitation of atomic vibrations. These phonons scatter with impurities, electrons, grain boundaries, and other phonons. At a sufficiently large scale, phonon dynamics can be approximated as a Brownian random walk, leading to ordinary diffusion described by the heat equation. However, such approximations fail at the scale of the phonon mean free path. In this regime, a proper wave description encoding phonon scattering is required. For sufficiently short thermal systems, the thermal conductivity becomes extrinsic and exhibits linear scaling with system size. This scale is known as the ballistic transport regime. As the system size grows beyond this scale, the thermal conductivity asymptotes into the intrinsic, ordinary diffusive regime. However, there are special circumstances where this transition does not occur. In this Thesis, we demonstrate the anomalous scaling of thermal conductivity. The source of this anomaly is the Anderson localization of thermal phonons. Anderson localization is the spatial trapping of waves due to extreme levels of elastic disorder. The hallmark of Anderson localization is an exponential decay law of conductance with increasing system size. Since thermal transport is a broadband process, this exponential suppression leads to a thermal conductivity maximum as a function of system size. Our numerical study of GaAs/AlAs superlattices with ErAs nanoparticles exhibits this thermal conductivity maximum, yielding quantitative agreement to experiments. We then generalize our elastic model to allow for the incorporation of finite-temperature effects. The inclusion of phonon-phonon scattering decoheres phonons, resulting in phonon delocalization. Counterintuitively, the additional inelastic scattering increases conductance for originally localized phonons. This localization to diffusive transition as a function of temperature is captured in our model at low temperatures (~20K).

50 Years of Anderson Localization

50 Years of Anderson Localization
Author :
Publisher : World Scientific
Total Pages : 610
Release :
ISBN-10 : 9789814299077
ISBN-13 : 9814299073
Rating : 4/5 (77 Downloads)

Synopsis 50 Years of Anderson Localization by : Elihu Abrahams

This unique volume celebrates the five decades of the impact of Anderson localization on modern physics. In addition to the historical perspective on its origin, it provides a comprehensive description of the experimental and theoretical aspects of Anderson localization.

Phonons in Low Dimensional Structures

Phonons in Low Dimensional Structures
Author :
Publisher : BoD – Books on Demand
Total Pages : 176
Release :
ISBN-10 : 9781789846263
ISBN-13 : 1789846269
Rating : 4/5 (63 Downloads)

Synopsis Phonons in Low Dimensional Structures by : Vasilios N. Stavrou

The field of low-dimensional structures has been experiencing rapid development in both theoretical and experimental research. Phonons in Low Dimensional Structures is a collection of chapters related to the properties of solid-state structures dependent on lattice vibrations. The book is divided into two parts. In the first part, research topics such as interface phonons and polaron states, carrier-phonon non-equilibrium dynamics, directional projection of elastic waves in parallel array of N elastically coupled waveguides, collective dynamics for longitudinal and transverse phonon modes, and elastic properties for bulk metallic glasses are related to semiconductor devices and metallic glasses devices. The second part of the book contains, among others, topics related to superconductor, phononic crystal carbon nanotube devices such as phonon dispersion calculations using density functional theory for a range of superconducting materials, phononic crystal-based MEMS resonators, absorption of acoustic phonons in the hyper-sound regime in fluorine-modified carbon nanotubes and single-walled nanotubes, phonon transport in carbon nanotubes, quantization of phonon thermal conductance, and phonon Anderson localization.

Non-Fourier Heat Conduction

Non-Fourier Heat Conduction
Author :
Publisher : Springer Nature
Total Pages : 419
Release :
ISBN-10 : 9783031259739
ISBN-13 : 3031259734
Rating : 4/5 (39 Downloads)

Synopsis Non-Fourier Heat Conduction by : Alexander I. Zhmakin

This book presents a broad and well-structured overview of various non-Fourier heat conduction models. The classical Fourier heat conduction model is valid for most macroscopic problems. However, it fails when the wave nature of the heat propagation becomes dominant and memory or non-local spatial effects become significant; e.g., during ultrafast heating, heat transfer at the nanoscale, in granular and porous materials, at extremely high values of the heat flux, or in heat transfer in biological tissues. The book looks at numerous non-Fourier heat conduction models that incorporate time non-locality for materials with memory, such as hereditary materials, including fractional hereditary materials, and/or spatial non-locality, i.e. materials with a non-homogeneous inner structure. Beginning with an introduction to classical transport theory, including phase-lag, phonon, and thermomass models, the book then looks at various aspects of relativistic and quantum transport, including approaches based on the Landauer formalism as well as the Green-Kubo theory of linear response. Featuring an appendix that provides an introduction to methods in fractional calculus, this book is a valuable resource for any researcher interested in theoretical and numerical aspects of complex, non-trivial heat conduction problems.

Anderson Localization

Anderson Localization
Author :
Publisher : Springer
Total Pages : 396
Release :
ISBN-10 : UOM:39015017210280
ISBN-13 :
Rating : 4/5 (80 Downloads)

Synopsis Anderson Localization by : Tsuneya Andō

Artificial Intelligence for Materials Science

Artificial Intelligence for Materials Science
Author :
Publisher : Springer Nature
Total Pages : 231
Release :
ISBN-10 : 9783030683108
ISBN-13 : 3030683109
Rating : 4/5 (08 Downloads)

Synopsis Artificial Intelligence for Materials Science by : Yuan Cheng

Machine learning methods have lowered the cost of exploring new structures of unknown compounds, and can be used to predict reasonable expectations and subsequently validated by experimental results. As new insights and several elaborative tools have been developed for materials science and engineering in recent years, it is an appropriate time to present a book covering recent progress in this field. Searchable and interactive databases can promote research on emerging materials. Recently, databases containing a large number of high-quality materials properties for new advanced materials discovery have been developed. These approaches are set to make a significant impact on human life and, with numerous commercial developments emerging, will become a major academic topic in the coming years. This authoritative and comprehensive book will be of interest to both existing researchers in this field as well as others in the materials science community who wish to take advantage of these powerful techniques. The book offers a global spread of authors, from USA, Canada, UK, Japan, France, Russia, China and Singapore, who are all world recognized experts in their separate areas. With content relevant to both academic and commercial points of view, and offering an accessible overview of recent progress and potential future directions, the book will interest graduate students, postgraduate researchers, and consultants and industrial engineers.

Handbook of Acoustics

Handbook of Acoustics
Author :
Publisher : John Wiley & Sons
Total Pages : 1494
Release :
ISBN-10 : 047125293X
ISBN-13 : 9780471252931
Rating : 4/5 (3X Downloads)

Synopsis Handbook of Acoustics by : Malcolm J. Crocker

Acoustical engineers, researchers, architects, and designers need a comprehensive, single-volume reference that provides quick and convenient access to important information, answers and questions on a broad spectrum of topics, and helps solve the toughest problems in acoustical design and engineering. The Handbook of Acoustics meets that need. It offers concise coverage of the science and engineering of acoustics and vibration. In more than 100 clearly written chapters, experts from around the world share their knowledge and expertise in topics ranging from basic aerodynamics and jet noise to acoustical signal processing, and from the interaction of fluid motion and sound to infrasound, ultrasonics, and quantum acoustics. Topics covered include: * General linear acoustics * Nonlinear acoustics and cavitation * Aeroacoustics and atmospheric sound * Mechanical vibrations and shock * Statistical methods in acoustics * Architectural acoustics * Physiological acoustics * Underwater sound * Ultrasonics, quantum acoustics, and physical aspects of sound * Noise: its effects and control * Acoustical signal processing * Psychological acoustics * Speech communication * Music and musical acoustics * Acoustical measurements and instrumentation * Transducers The Handbook of Acoustics belongs on the reference shelf of every engineer, architect, research scientist, or designer with a professional interest in the propagation, control, transmission, and effects of sound.

Phonons in Low Dimensional Structures

Phonons in Low Dimensional Structures
Author :
Publisher :
Total Pages : 174
Release :
ISBN-10 : 1789846277
ISBN-13 : 9781789846270
Rating : 4/5 (77 Downloads)

Synopsis Phonons in Low Dimensional Structures by : Vasilios N. Stavrou

The field of low-dimensional structures has been experiencing rapid development in both theoretical and experimental research. Phonons in Low Dimensional Structures is a collection of chapters related to the properties of solid-state structures dependent on lattice vibrations. The book is divided into two parts. In the first part, research topics such as interface phonons and polaron states, carrier-phonon non-equilibrium dynamics, directional projection of elastic waves in parallel array of N elastically coupled waveguides, collective dynamics for longitudinal and transverse phonon modes, and elastic properties for bulk metallic glasses are related to semiconductor devices and metallic glasses devices. The second part of the book contains, among others, topics related to superconductor, phononic crystal carbon nanotube devices such as phonon dispersion calculations using density functional theory for a range of superconducting materials, phononic crystal-based MEMS resonators, absorption of acoustic phonons in the hyper-sound regime in fluorine-modified carbon nanotubes and single-walled nanotubes, phonon transport in carbon nanotubes, quantization of phonon thermal conductance, and phonon Anderson localization.

Thermal Conductivity

Thermal Conductivity
Author :
Publisher : Springer Science & Business Media
Total Pages : 306
Release :
ISBN-10 : 9780387260174
ISBN-13 : 038726017X
Rating : 4/5 (74 Downloads)

Synopsis Thermal Conductivity by : Terry M. Tritt

It has been almost thirty years since the publication of a book that is entirely dedicated to the theory, description, characterization and measurement of the thermal conductivity of solids. The recent discovery of new materials which possess more complex crystal structures and thus more complicated phonon scattering mechanisms have brought innovative challenges to the theory and experimental understanding of these new materials. With the development of new and novel solid materials and new measurement techniques, this book will serve as a current and extensive resource to the next generation researchers in the field of thermal conductivity. This book is a valuable resource for research groups and special topics courses (8-10 students), for 1st or 2nd year graduate level courses in Thermal Properties of Solids, special topics courses in Thermal Conductivity, Superconductors and Magnetic Materials, and to researchers in Thermoelectrics, Thermal Barrier Materials and Solid State Physics.

Mesoscopic Physics of Phonon Transport in Carbon Materials

Mesoscopic Physics of Phonon Transport in Carbon Materials
Author :
Publisher :
Total Pages :
Release :
ISBN-10 : OCLC:1154229853
ISBN-13 :
Rating : 4/5 (53 Downloads)

Synopsis Mesoscopic Physics of Phonon Transport in Carbon Materials by : Kenji Sasaoka

We give a theoretical review of recent development of the mesoscopic physics of phonon transport in carbon nanotubes, including the quantization of phonon thermal conductance, phonon Anderson localization, and so on. A single-walled carbon nanotube (SWCNT) can be regarded as a typical one-dimensional phonon conductor and exhibits various interesting phenomena originating from its one dimensionality. For example, a pristine SWCNT without any defects shows the quantization of phonon thermal conductance at low temperature. On the other hand, a defective SWCNT with randomly distributed carbon isotopes shows the phonon Anderson localization originating from the interference between phonons scattered by isotope impurities.