Oxygenation‐Induced Two‐Dimensional Topological Insulators in Antimony Arsenide

Abstract

This study investigates the stability, electronic structure, and topological property of a fully oxygenated blue‐antimony arsenide system based on first principle calculations. Our results demonstrate that the functionalized system is energetically, dynamically, and mechanically stable. Without the inclusion of spin–orbit coupling (SOC), a semimetal nature is observed with the degenerate valence and conduction bands at the Γ point. The SOC opens a large bulk gap of 252 meV, which makes it possible to work at room temperature. The nontrivial topological feature is confirmed by the Z2 topological invariant Z2 = 1 and the gapless edge states inside the bulk gap. This finding enriches the family of 2D topological insulators, deepens the insight into the quantum Hall effect, and provides some theoretical ideas for preparing high‐speed and dissipationless spintronic devices.