Native Point Defects in Boron Arsenide.

We present $ab$ $initio$ results for structure and energetics of native point defects in BAs and examine their effect on its thermal conductivity, predicted to be ultrahigh. We find that antisites are the constitutional defects in B-rich and As-rich material, while B$_\mathrm{As}$ antisites and B vacancies dominate stoichiometry. With the thermodynamically correct point defects treated as mass defects, extrapolation of experimental results for non-stoichiometric samples to perfect crystals suggests that the BAs thermal conductivity should indeed reach the theoretically predicted 2000 W/(mK), rivaling diamond.