Optical properties of cubic boron arsenide

TL;DR

This study provides comprehensive experimental and theoretical insights into the optical properties of cubic boron arsenide, highlighting its potential for advanced electronic and optoelectronic applications due to its exceptional thermal and electronic characteristics.

Contribution

It offers the first detailed measurement and theoretical calculation of optical properties of cubic boron arsenide, including dielectric function, refractive index, and band gaps.

Findings

Measured optical properties align with theoretical predictions.

Direct and indirect band gaps are approximately 4.12 eV and 2.02 eV.

Results support boron arsenide's use in high-performance optoelectronic devices.

Abstract

The ultrahigh thermal conductivity of boron arsenide makes it a promising material for next-generation electronics and optoelectronics. In this work, we report measured optical properties of cubic boron arsenide crystals including the complex dielectric function, refractive index, and absorption coefficient in the ultraviolet, visible, and near-infrared wavelength range. The data were collected at room temperature using spectroscopic ellipsometry as well as transmission and reflection spectroscopy. We further calculate the optical response using density functional and many-body perturbation theory, considering quasiparticle and excitonic corrections. The computed values for the direct and indirect band gaps (4.25 eV and 2.07 eV) agree well with the measured results (4.12 eV and 2.02 eV). Our findings contribute to the effort of using boron arsenide in novel electronic and optoelectronic applications that take advantage of its demonstrated ultrahigh thermal conductivity and predicted high ambipolar carrier mobility.