Intrinsic Ferromagnetism in 2D Fe<sub>2</sub>H with a High Curie Temperature
Shicong Ding, Xu Yan, Aitor Bergara, Xiaohua Zhang, Yong Liu, Guochun Yang
Abstract
The rational design of ferromagnetic materials is crucial for the development of spintronic devices. Using first-principles structural search calculations, we have identified 73 two-dimensional transition metal hydrides. Some of them show interesting magnetic properties, even when combined with the characteristics of the electrides. In particular, the P3̅m1 Fe2H monolayer is stabilized in a 1T-MoS2-type structure with a local magnetic moment of 3 μB per Fe atom, whose robust ferromagnetism is attributed to the exchange interaction between neighboring Fe atoms within and between sublayers, leading to a remarkably high Curie temperature of 340 K. On the other hand, it has a large magnetic anisotropic energy and spin-polarization ratio. Interestingly, the above room-temperature ferromagnetism of the Fe2H monolayer is well preserved within a biaxial strain of 5%. The structure and electron property of surface-functionalized Fe2H are also explored. All of these interesting properties make the Fe2H monolayer an attractive candidate for spintronic nanodevices.