High-temperature quantum spin Hall states in buckled III-V-monolayer/SiO$_{2}

TL;DR

This paper proposes a new family of III-V honeycomb monolayers on SiO2 that exhibit large-gap quantum spin Hall states, potentially enabling room-temperature spintronic devices with robust topological properties.

Contribution

It introduces a novel class of III-V monolayers on SiO2 with large topological gaps, distinct from Kane-Mele type insulators, advancing the search for practical room-temperature topological insulators.

Findings

Enlarged topological gap (~900 meV) in proposed monolayers.

Realization of band-inversion type QSH insulator.

Potential for room-temperature spintronic applications.

Abstract

After establishing the fundamental understanding and the high throughput topological characterization of nearly all inorganic three-dimensional materials, the general interest and the demand of functional applications drive the research of topological insulators to the exploration of systems with a more robust topological nature and fewer fabrication challenges. The successful demonstration of the room-temperature quantum spin Hall (QSH) states in bismuthene/SiC(0001), thus, triggers the search of two-dimensional topological systems that are experimentally easy to access and of even larger topological gaps. In this work, we propose a family of III-V honeycomb monolayers on SiO$_{2}$ to be the next generation of large gap QSH systems, based on which a spintronic device may potentially operate at room temperature due to its enlarged topological gap ($\sim$ 900 meV) as compared to bismuthene/SiC(0001). Fundamentally, this also realizes a band-inversion type QSH insulator that is distinct to the Kane-Mele type bismuthene/SiC(0001).