Quantum anomalous Hall insulator phases in Fe-doped GaBi honeycomb

Authors

Zhi-Quan Huang; Chia-Hsiu Hsu; Christian P. Crisostomo; Gennevieve Macam; Jing-Rong Su; Hsin Lin; Arun Bansil; Feng-Chuan Chuang

Source

Chinese J. Phys. 67, 246 (2020). DOI: 10.1016/j.cjph.2020.07.007

Abstract

We discuss electronic and magnetic properties of the Fe-doped GaBi honeycomb using first principles calculations. Our analysis shows that the pristine GaBi honeycomb transitions from being a two-dimensional quantum spin Hall (QSH) insulator to a quantum anomalous Hall (QAH) insulator when it is doped with one Fe atom in a 4 × 4 GaBi honeycomb. The QAH phase in Fe-doped GaBi is found to be robust in that it maintains its Chern number (C = 1) under fairly large strains (∼ 4%) and supports a gap as large as 112 meV at 2.21% strain. The QAH phase is also retained when the Fe-doped GaBi is placed on a CdTe substrate, suggesting that Fe-doped GaBi films could be useful for spintronics applications.