High-temperature quantum anomalous Hall effect in honeycomb bilayer consisting of Au atoms and single-vacancy graphene

Abstract

The quantum anomalous Hall effect (QAHE) is predicted to be realized at high temperature in a honeycomb bilayer consisting of Au atoms and single-vacancy graphene (Au 2 -SVG) based on the first-principles calculations. We demonstrate that the ferromagnetic state in the Au 2 -SVG can be maintained up to 380 K. The combination of spatial inversion symmetry and the strong SOC introduced by the Au atoms causes a topologically nontrivial band gap as large as 36 meV and a QAHE state with Chern number C = -2. The analysis of the binding energy proved that the honeycomb bilayer is stable and feasible to be fabricated in experiment. The QAHEs in Ta 2 -SVG and other TM 2 -SVGs are also discussed.