First-principle calculations of phononic, electronic and optical properties of monolayer arsenene and antimonene allotropes

TL;DR

This study uses first-principles calculations to explore the phononic, electronic, and optical properties of monolayer arsenene and antimonene allotropes, revealing their stability and potential applications in optoelectronics.

Contribution

It provides a systematic analysis of four monolayer arsenene and antimonene allotropes, including their stability, electronic band structure, and optical absorption characteristics.

Findings

Monolayer $eta$-As and $eta$-Sb have indirect band gaps.

Monolayer $ ext{α}$-As and $ ext{α}$-Sb have direct band gaps.

Significant optical absorption observed in $ ext{α}$-Sb.

Abstract

Recently a stable monolayer of antimony in buckled honeycomb structure called antimonene was successfully grown on 3D topological insulator Bi$_2$Te$_3$ and Sb$_2$Te$_3$, which displays semiconducting properties. By first principle calculations, we systematically investigate the phononic, electronic and optical properties of $\alpha-$ and $\beta-$ allotropes of monolayer arsenene/antimonene. We investigate the dynamical stabilities of these four materials by considering the phonon dispersions. The obtained electronic structures reveal the direct band gap of monolayer $\alpha-$As/Sb and indirect band gap of $\beta-$As/Sb. Significant absorption is observed in $\alpha-$Sb, which can be used as a broad saturable absorber.