Quantized anomalous Hall insulator in a nanopatterned two-dimensional electron gas

Abstract

We propose that a quantum anomalous Hall insulator (QAHI) can be realized in a nanopatterned two-dimensional electron gas (2DEG) with a small in-plane magnetic field and a high carrier density. The Berry curvatures originating from the in-plane magnetic field and Rashba and Dresselhaus spin-orbit coupling, in combination with a nanoscale honeycomb lattice potential modulation, lead to topologically nontrivial insulating states in the 2DEG without Landau levels. In the bulk insulating gaps, the anomalous Hall conductivity is quantized $\ensuremath{-}{e}^{2}/h$, corresponding to a finite Chern number $\ensuremath{-}1$. There exists one gapless chiral edge state on each edge of a finite-size 2DEG.