Cubic BAs has received recent attention for its large electron and hole mobilities and large thermal conductivity. This is a rare and much desired combination in semiconductor industry: commercial semiconductors typically have high electron mobilities, or hole mobilities, or large thermal conductivities, but not all of them together. Here we report predictions from an advanced self-consistent many body perturbative theory and show that with respect to one-particle properties, BAs is strikingly similar to Si. There are some important differences, notably there is an unusually small variation in the valence band masses . With respect to two-particle properties, significant differences with Si appear. We report the excitonic spectrum for both q=0 and finite q, and show that while the direct gap in cubic BAs is about 4 eV, dark excitons can be observed down to about ∼1.5 eV, which may play a crucial role in application of BAs in optoelectronics.
@article{arxiv.2305.17215,
title = {One-particle and excitonic band structure in cubic Boron Arsenide},
author = {Swagata Acharya and Dimitar Pashov and Mikhail I Katsnelson and Mark van Schilfgaarde},
journal= {arXiv preprint arXiv:2305.17215},
year = {2023}
}