English
Related papers

Related papers: Phonon hydrodynamic regimes in sapphire

200 papers

The Chapman-Enskog method is generalized for accounting the effect of kinetic modes on hydrodynamic evolution. Hydrodynamic states of phonon system of insulators have been studied in a small drift velocity approximation. For simplicity, the…

Statistical Mechanics · Physics 2012-12-27 S. A. Sokolovsky

A review of electronic properties of insulating-, boron- and phosphorus-doped diamond is given. The main goal is, to show data in a wider context, to reveal trends and limitations with respect to carrier mobilities, conductivities, p- and…

Materials Science · Physics 2020-05-11 Christoph E. Nebel

The lattice thermal conductivity and thermal transport properties of 2D $\alpha$-selenene are investigated based on the first-principles calculations. The isotropic in-plane thermal conductivity is as low as 3.04 W m$^{-1}$ K$^{-1}$ at room…

Computational Physics · Physics 2020-01-30 Gang Liu , Zhibin Gao , Guo-Ling Li , Hui Wang

Surface phonon-polaritons can carry energy on the surface of dielectric films and thus are expected to contribute to heat conduction. However, the contribution of surface phonon-polaritons (SPhPs) to thermal transport has not been…

Mesoscale and Nanoscale Physics · Physics 2019-08-06 Yunhui Wu , Jose Ordonez-Miranda , Sergei Gluchko , Roman Anufriev , Sebastian Volz , Masahiro Nomura

By way of the nonequilibrium Green's function simulations and first principles calculations, we report that borophene, a single layer of boron atoms that was fabricated recently, possesses an extraordinarily high lattice thermal conductance…

Materials Science · Physics 2017-05-31 Hangbo Zhou , Yongqing Cai , Gang Zhang , Yong-Wei Zhang

We have calculated the temperature profiles for phonon heat transport in a suspended membrane with a radially symmetric heat source in the two extreme cases of either fully ballistic or fully diffusive transport. Theoretical results confirm…

Mesoscale and Nanoscale Physics · Physics 2012-04-03 J. T. Karvonen , T. Kühn , I. J. Maasilta

We calculate the lattice thermal conductivities of the pyrite-type ZnSe2 at pressures of 0 and 10 GPa using the linearized phonon Boltzmann transport equation. We obtain a very low value [0.69 W/(mK) at room temperature at 0 GPa],…

Materials Science · Physics 2020-10-07 Tiantian Jia , Jesus Carrete , Zhenzhen Feng , Shuping Guo , Yongsheng Zhang , Georg K. H. Madsen

Semi-crystalline polymers have been shown to have greatly increased thermal conductivity compared to amorphous bulk polymers due to effective heat conduction along the covalent bonds of the backbone. However, the mechanisms governing the…

Mesoscale and Nanoscale Physics · Physics 2015-12-09 Andrew B. Robbins , Austin J. Minnich

We present a study of electrical and thermal transport in Weyl semimetal WTe$_2$ down to 0.3 K. The Wiedemann-Franz law holds below 2 K and a downward deviation starts above. The deviation is more pronounced in cleaner samples, as expected…

Mesoscale and Nanoscale Physics · Physics 2024-08-26 Wei Xie , Feng Yang , Liangcai Xu , Xiaokang Li , Zengwei Zhu , Kamran Behnia

We develop the theory of hydrodynamics of an isotropic Fermi liquid of electrons coupled to isotropic acoustic phonons, assuming that umklapp processes may be neglected. At low temperatures, the fluid is approximately Galilean invariant; at…

Strongly Correlated Electrons · Physics 2021-07-15 Xiaoyang Huang , Andrew Lucas

We calculate the thermal conductivity of free-standing silicene using the phonon Boltzmann transport equation within the relaxation time approximation. In this calculation, we investigate the effects of sample size and different scattering…

Mesoscale and Nanoscale Physics · Physics 2018-04-18 M. Barati , T. Vazifehshenas , T. Salavati-fard , M. Farmanbar

In the hydrodynamic regime, phonons drift with a nonzero collective velocity under a temperature gradient, reminiscent of viscous gas and fluid flow. The study of hydrodynamic phonon transport has spanned over half a century but has been…

Materials Science · Physics 2018-02-05 Zhiwei Ding , Jiawei Zhou , Bai Song , Vazrik Chiloyan , Mingda Li , Te-Huan Liu , Gang Chen

A first-principles density functional method along with the direct solution of linearized Boltzmann transport equations are employed to systematically analyze the low-temperature thermal transport in crystalline GeTe. The extensive thermal…

Materials Science · Physics 2020-09-28 Kanka Ghosh , Andrzej Kusiak , Jean-Luc Battaglia

We investigate the effect of confinement and orientation on the phonon transport properties of ultra-thin silicon layers of thicknesses between 1 nm-16 nm. We employ the modified valence force field method to model the lattice dynamics and…

Mesoscale and Nanoscale Physics · Physics 2013-06-12 Hossein Karamitaheri , Neophytos Neophytou , Hans Kosina

Phosphorene has attracted tremendous interest recently due to its intriguing electronic properties. However, the thermal transport properties of phosphorene, especially for its allotropes, are still not well-understood. In this work, we…

Mesoscale and Nanoscale Physics · Physics 2016-04-08 J. Zhang , H. J. Liu , L. Cheng , J. Wei , J. H. Liang , D. D. Fan , P. H. Jiang , J. Shi

The phonon thermal transport properties of twisted bi-layer graphene are investigated using lattice dynamics and the Boltzmann transport equation. The thermal conductivities of 13.2 and 21.8 twisted configurations are 56% and 36% lower than…

Mesoscale and Nanoscale Physics · Physics 2023-11-07 Shahid Ahmed , Shadab Alam , Ankit Jain

We present a study of thermal conductivity, $\kappa$, in undoped and doped strontium titanate in a wide temperature range (2-400 K) and detecting different regimes of heat flow. In undoped SrTiO$_{3}$, $\kappa$ evolves faster than cubic…

In this work, the effects of Si/Al ratio and moisture content on thermal transport in sustainable geopolymers has been comprehensively investigated by using the molecular dynamics simulation. The thermal conductivity of geopolymer systems…

Soft Condensed Matter · Physics 2024-05-01 Wenkai Liu , Shenghong Ju

The thermal conductivity of polycrystalline samples of (Na,Ca)Co_2O_4 is found to be unusually low, 20 mW/cmK at 280 K. On the assumption of the Wiedemann-Franz law, the lattice thermal conductivity is estimated to be 18 mW/cmK at 280 K,…

Strongly Correlated Electrons · Physics 2009-10-31 K. Takahata , Y. Iguchi , D. Tanaka , T. Itoh , I. Terasaki

The lattice thermal conductivity ($\kappa$) of two ceramic materials, cerium dioxide (CeO$_2$) and magnesium oxide (MgO), is computed up to 1500 K using first principles and the phonon Boltzmann Transport Equation (PBTE) and compared to…