First-Principles Determination of Ultrahigh Thermal Conductivity of Boron Arsenide: A Competitor for Diamond?

We have calculated the thermal conductivities ($\ensuremath{\kappa}$) of cubic III-V boron compounds using a predictive first principles approach. Boron arsenide is found to have a remarkable room temperature $\ensuremath{\kappa}$ over $2000\text{ }\text{ }\mathrm{W}\text{ }{\mathrm{m}}^{\ensuremath{-}1}\text{ }{\mathrm{K}}^{\ensuremath{-}1}$; this is comparable to those in diamond and graphite, which are the highest bulk values known. We trace this behavior in boron arsenide to an interplay of certain basic vibrational properties that lie outside of the conventional guidelines in searching for high $\ensuremath{\kappa}$ materials, and to relatively weak phonon-isotope scattering. We also find that cubic boron…

• NS
  National Science Foundation
• UD
  U.S. Department of Energy