Chern insulator in a ferromagnetic two-dimensional electron system with Dresselhaus spin–orbit coupling

Abstract

We propose a Chern insulator in a two-dimensional electron system with Dresselhaus spin–orbit coupling, ferromagnetism, and spin-dependent effective mass. The analytically-obtained topological phase diagrams show the topological phase transitions induced by tuning the magnetization orientation with the Chern number varying between 1, 0, −1. The magnetization orientation tuning shown here is a more practical way of triggering the topological phase transitions than manipulating the exchange coupling that is no longer tunable after the fabrication of the system. The analytic results are confirmed by the band structure and transport calculations, showing the feasibility of this theoretical proposal. With the advanced and mature semiconductor engineering today, this Chern insulator is very possible to be experimentally realized and also promising to topological spintronics.

Keywords

• topological phase transition
• quantum anomalous Hall effect
• Chern insulator
• nonequilibrium Green function
• semiconductor heterostructure
• spintronics