Cr doped topological insulator Bi2Se3 under external electric field: A first-principle study

33rd International Conference on the Physics of Semiconductors

Lian, Ruqian^1,2 ; Zhang, Jian-Min^1,2 ; Yang, Yanmin^1,2 ; Xu, Guigui^1,2 ; Zhong, Kehua^1,2 ; Huang, Zhigao^1,2

Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou

350117, China^1

Fujian Prov. Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen

361005, China^2

关键词: Cr atoms;    Cr-doped;    External electric field;    First-principle study;    First-principles calculation;    Spin-orbital coupling;    Spintronic applications;    Topological insulators;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/864/1/012039/pdf
DOI  :  10.1088/1742-6596/864/1/012039

来源: IOP

【 摘 要 】

In this paper, we investigated the magnetic topological insulator (MTI) Cr-doped Bi2Se3film using first principles calculations based on the density functional theory (DFT). The band structure of Cr doped 3QL-Bi2Se3film was calculated comparing with pure Bi2Se3film. Our results demonstrate that the doping of Cr atom changes the degenerate surface state of pure Bi2Se3, inducing the ferromagnetism. Under the external electric field, the band gap of pure Bi2Se3films is determined by the charge transfer and the effect of spin-orbital coupling (SOC). For the MTI, the electric field will redistribute the electrons and enhance the magnetism. Our results will further promote the development of the electronic and spintronic applications of topological insulator.