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arXiv · 2305.17215

One-particle and excitonic band structure in cubic Boron Arsenide

Swagata Acharya·Dimitar Pashov·Mikhail I Katsnelson·Mark van Schilfgaarde
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Abstract

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 $\sim$1.5 eV, which may play a crucial role in application of BAs in optoelectronics.

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Swagata Acharya, Dimitar Pashov, Mikhail I Katsnelson, Mark van Schilfgaarde. 2023-05-26. One-particle and excitonic band structure in cubic Boron Arsenide. https://doi.org/10.1002/pssr.202300156

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