Phonon transport in square-cross-section nanowires is studied using spectral Monte Carlo simulations. Our results show the evolution of the different transport regimes described by Lévy statistics as a function of the surface roughness-to-thermal wavelength ratio σ/λ. More precisely, the relationship between the Lévy index γ describing the mean free path distribution Ψ(Λ) and σ/λ is established for the classical diffusive regime, the superdiffusive regime, and the ballistic regime in the nanowire. Besides the conventional superdiffusive regime that is marked by Ψ(Λ) with a single heavy-tailed peak, we reveal an unconventional superdiffusive subregime featuring Ψ(Λ) with sawtooth oscillations when σ/λ∼0.01. Investigation of the direction of propagation of phonons shows a significant narrowing of the angular distribution around the long axis of the nanowire due to the diffuse scattering at rough boundaries when σ/λ>0.1. These results shed light on the transport mechanisms of quasiballistic phonons and will help in nanowire design for specific applications.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevE.105.064123 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Quasiballistic thermal transport in submicron-scale graphene nanoribbons at room-temperature.
Nanoscale Adv
May 2024
School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) Buk-gu Gwangju 61005 Korea
Phonon transport in two-dimensional materials has been the subject of intensive studies both theoretically and experimentally. Recently observed unique phenomena such as Poiseuille flow at low temperature in graphene nanoribbons (GNRs) initiated strong interest in similar effects at higher temperatures. Here, we carry out massive molecular dynamics simulations to examine thermal transport in GNRs at room temperature (RT) and demonstrate that non-diffusive behaviors including Poiseuille-like local thermal conductivity and second sound are obtained, indicating quasiballistic thermal transport.
View Article and Find Full Text PDFTheory of acoustic polarons in the two-dimensional SSH model applied to the layered superatomic semiconductor Re6Se8Cl2.
J Chem Phys
May 2024
Department of Chemistry, Columbia University, New York, New York 10027, USA.
Layered superatomic semiconductors, whose building blocks are atomically precise molecular clusters, exhibit interesting electronic and vibrational properties. In recent work [Tulyagankhodjaev et al., Science 382, 438 (2023)], transient reflection microscopy revealed quasi-ballistic exciton dynamics in Re6Se8Cl2, which was attributed to the formation of polarons due to coupling with acoustic phonons.
View Article and Find Full Text PDFAnisotropy Reversal of Thermal Conductivity in Silicon Nanowire Networks Driven by Quasi-Ballistic Phonon Transport.
ACS Nano
April 2024
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan.
Nanostructured semiconductors promise functional thermal management for microelectronics and thermoelectrics through a rich design capability. However, experimental studies on anisotropic in-plane thermal conduction remain limited, despite the demand for directional heat dissipation. Here, inspired by an oriental wave pattern, a periodic network of bent wires, we investigate anisotropic in-plane thermal conduction in nanoscale silicon phononic crystals with the thermally dead volume.
View Article and Find Full Text PDFRoom-temperature wavelike exciton transport in a van der Waals superatomic semiconductor.
Science
October 2023
Department of Chemistry, Columbia University, New York, NY 10027, USA.
The transport of energy and information in semiconductors is limited by scattering between electronic carriers and lattice phonons, resulting in diffusive and lossy transport that curtails all semiconductor technologies. Using ReSeCl, a van der Waals (vdW) superatomic semiconductor, we demonstrate the formation of acoustic exciton-polarons, an electronic quasiparticle shielded from phonon scattering. We directly imaged polaron transport in ReSeCl at room temperature, revealing quasi-ballistic, wavelike propagation sustained for a nanosecond and several micrometers.
View Article and Find Full Text PDFStrong Electron-Phonon Coupling Mediates Carrier Transport in BiFeO.
Adv Sci (Weinh)
August 2023
School of Physics and Technology, Center for Nanoscience and Nanotechnology, and Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Wuhan University, Wuhan, 430072, China.
The electron-phonon interaction is known as one of the major mechanisms determining electrical and thermal properties. In particular, it alters the carrier transport behaviors and sets fundamental limits to carrier mobility. Establishing how electrons interact with phonons and the resulting impact on the carrier transport property is significant for the development of high-efficiency electronic devices.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!