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.

Effect of Magnetic Tuning and Induced Charge Transfer Isotropy in a CrI3-Based 2D Trilayer Heterostructure

“…63 Graphene is found to remain nonmagnetic with a magnetic moment localized on the ferromagnetic CrI 3 layer. We find that as the Dirac cone split (for the spin-down case) lies within the bandgap of CrI 3 , one can predict that graphene behaves as a novel spin-selective Chern insulator 35,64 in the designed trilayer.…”

Shift photoconductivity in the Haldane model

“…The above suggests that the sign reversal of the shift current across the topological phase transition is a robust effect that might therefore be experimentally observed in real topological insulators. The pool of materials include two-dimensional quantum anomalous Hall systems such as thin films of Crdoped (BiSe) 2 Te 3 [50] and interfaces between ferromagnetic and nonmagnetic semiconductors [51] (see, e.g., Ref. [52] for more examples).…”