Thermal Conductivity of BAs under Pressure

Abstract

The thermal conductivity of boron arsenide (BAs) is believed to be influenced by phonon scattering selection rules due to its special phonon dispersion. Compression of BAs leads to significant changes in phonon dispersion, which allows for a test of first principles theories for how phonon dispersion affects three‐ and four‐phonon scattering rates. This study reports the thermal conductivity of BAs from 0 to 30 GPa. Thermal conductivity vs. pressure of BAs is measured by time‐domain thermoreflectance with a diamond anvil cell. In stark contrast to what is typical for nonmetallic crystals, BAs is observed to have a pressure independent thermal conductivity below 30 GPa. The thermal conductivity of nonmetallic crystals typically increases upon compression. The unusual pressure independence of BAs's thermal conductivity shows the important relationship between phonon dispersion properties and three‐ and four‐phonon scattering rates.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 22, 2022
Source ID
10.1002/aelm.202200017

Entities

People

  • Bo Sun
  • Chen Li
  • Fei Tian
  • Qingan Cai
  • Richard B Wilson
  • Shanmin Wang
  • Songrui Hou
  • Xi Chen
  • Youming Xu
  • Zhifeng Ren

Organizations

  • National Science Foundation
  • Office of Basic Energy Sciences
  • Office of Naval Research
  • Office of Science
  • Southern University of Science and Technology
  • Sun Yat-sen University
  • Tsinghua University
  • United States Department of Energy
  • University of California
  • University of Houston

Tags

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Thermal Physics or Thermal Science.