Cr2XTe4(X = Si, Ge) monolayers: a new type of two-dimensional high- TCIsing ferromagnetic semiconductors with a large magnetic anisotropy

Yihang Bai; Rui Shi; Yaxuan Wu; Bing Wang; Xiuyun Zhang

doi:10.1088/1361-648X/ac7f16

Cr₂XTe₄(X = Si, Ge) monolayers: a new type of two-dimensional high- T_CIsing ferromagnetic semiconductors with a large magnetic anisotropy

J Phys Condens Matter. 2022 Jul 18;34(38). doi: 10.1088/1361-648X/ac7f16.

Authors

Yihang Bai¹, Rui Shi², Yaxuan Wu¹, Bing Wang¹, Xiuyun Zhang³

Affiliations

¹ Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
² Patent Examination Cooperation (Henan) Center of the Patent Office, China National Intellectual Property Administration, Zhengzhou 450000, People's Republic of China.
³ College of Physics Science and Technology, Yangzhou University, Yangzhou 225002, People's Republic of China.

PMID: 35793684
DOI: 10.1088/1361-648X/ac7f16

Abstract

Two-dimensional (2D) ferromagnetic semiconductor (FMS) provides the ideal platform for the development of quantum information technology in nanoscale devices. However, most of them suffer from low Curie temperature and small magnetic anisotropic energy (MAE), severely limiting their practical application. In this work, by using first-principles calculations, we predicted two stable 2D materials, namely, Cr₂SiTe₄and Cr₂GeTe₄monolayers. Interestingly, both of them are intrinsic direct band gap FMSs (∼1 eV) with a large magnetization (8µ_Bf.u.^-1) and sizable MAE (∼500μ_eV Cr^-1). Monte Carlo simulations based on Heisenberg model suggest markedly high Curie temperatures of these monolayers (∼200 K). Besides, their high mechanical, dynamical, and thermal stabilities are further verified by elastic constants, phonon dispersion calculations, andab initiomolecular dynamics simulations. The outstanding attributes render Cr₂XTe₄(X = Si, Ge) monolayers broadening the candidates of 2D FMS for a wide range of applications.

Keywords: ferromagnetic semiconductor; high Curie temperature; magnetic anisotropy; spin–orbit coupling.