Conversation from antiferromagnetic MnBr2 to ferromagnetic Mn3Br8 monolayer with large MAE

Nanoscale Research Letters

S. Jin¹  X. L. Fan²  H. H. Zeng²  Y. Hu²  J. H. Wang²  Z. F. Luo² 

[1] Queen Mary University of London Engineering School, Northwestern Polytechnical University, 127 YouYi Western Road, 710072, Xi’an, Shaanxi, China;State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, 127 YouYi Western Road, 710072, Xi’an, Shaanxi, China;

关键词: First-principles calculations;    Ferromagnetism;    Two-dimensional (2D) materials;    Magnetic anisotropy energy (MAE);   

DOI  :  10.1186/s11671-021-03523-0

来源: Springer

【 摘 要 】

A pressing need in low energy spintronics is two-dimensional (2D) ferromagnets with Curie temperature above the liquid-nitrogen temperature (77 K), and sizeable magnetic anisotropy. We studied Mn3Br8 monolayer which is obtained via inducing Mn vacancy at 1/4 population in MnBr2 monolayer. Such defective configuration is designed to change the coordination structure of the Mn-d5 and achieve ferromagnetism with sizeable magnetic anisotropy energy (MAE). Our calculations show that Mn3Br8 monolayer is a ferromagnetic (FM) half-metal with Curie temperature of 130 K, large MAE of − 2.33 meV per formula unit, and atomic magnetic moment of 13/3μB for the Mn atom. Additionally, Mn3Br8 monolayer maintains to be FM under small biaxial strain, whose Curie temperature under 5% compressive strain is 160 K. Additionally, both biaxial strain and carrier doping make the MAE increases, which mainly contributed by the magneto-crystalline anisotropy energy (MCE). Our designed defective structure of MnBr2 monolayer provides a simple but effective way to achieve ferromagnetism with large MAE in 2D materials.

【 授权许可】

CC BY