Uncovering the Structural Evolution Arsenene on SiC Substrate

TL;DR

This paper reports the experimental growth of arsenene on SiC substrate, revealing a new strained triangular allotrope with semiconducting properties, supported by ab initio simulations.

Contribution

First experimental realization of arsenene on SiC, discovering a novel strained triangular structure with unique electronic properties.

Findings

Arsenene grown on SiC exhibits a flat, strained triangular structure.

The structure shows a Peierls-like transition with an indirect band gap.

Simulations confirm the experimental structural and electronic characteristics.

Abstract

Two-dimensional arsenic allotropes have been grown on metallic surfaces, while topological properties have been theoretically described on strained structures. Here we experimentally grow arsenene by molecular beam epitaxy over the insulating SiC substrate. The arsenene presents a flat structure with a strain field that follows the SiC surface periodicity. Our ab initio simulations, based on the density functional theory, corroborate the experimental observation. The strained structure presents a new arsenene allotrope with a triangular structure, rather than the honeycomb previously predicted for other pnictogens. This strained structure presents a Peierls-like transition leading to an indirect gap semiconducting behavior.