Tunable surface magnetism by gate voltage in a slab of nonmagnetic half-Heusler compound CoTiSb.
He SunLiwei JiangYisong ZhengPublished in: The Journal of chemical physics (2023)
The electrical manipulation of magnetization is appealing to the relevant experiment and spintronic device. In this paper, we focus on the electrical and magnetic properties of a thin film cleaved from the nonmagnetic half-Heusler compound CoTiSb. By means of the first-principles calculations, we find that the surface of TiSb termination possesses ferrimagnetism with a magnetic moment of 0.35 (0.49) μ B per unit cell without (with) Hubbard U, which can persist below the Curie temperature of 48 (54) K. What is more, such a surface magnetism can be tuned to nonmagnetism by gate-induced hole doping with a concentration of 2.83 × 10 14 (3.55 × 10 14 ) cm -2 . This magnetic tunability of the CoTiSb slab provides a platform to realize the pseudo-spin valve with both the magnetic electrodes and nonmagnetic space layer made of the same material without hetero-interfaces.