Interatomic doping regulating the electronic structure and magnetic anisotropy of MnI3 monolayer: A first-principles study

Abstract

As a member of the two-dimensional transition metal trihalide (MX3) family, the MnI3 monolayer has recently garnered significant attention due to its unique intrinsic ferromagnetic half-metallic properties and high Curie temperature. However, its inherent in-plane magnetization preference limits its potential applications in spintronics. To address this issue, in this work, we investigate the effects of 3d transition metal V and Cr doping on the electronic structure and magnetic properties of the MnI3 monolayer. The results show that the doped systems exhibit excellent structural stability and out-of-plane ferromagnetic semiconductor properties. In the VMn2I6 and CrMn2I6 monolayer, the adsorption energy can reach −8.421 and −5.796 eV/atom, respectively, and the large magnetic anisotropy energies flip their easy magnetization axis along the z-direction successfully. Moreover, the semiconductor bandgaps can increase to 2.51 and 1.26 eV relative to half-metal MnI3 monolayer. Bader charge analysis reveals that V and Cr doping enhance charge transfer in the MnI3 monolayer and increase the magnetic moment of Mn ions to approximately 4.6 μB. The interstitial doping significantly changes the exchange interactions path between magnetic atoms, leading to a noticeable reduction in the Curie temperature. This work provides an effective approach and theoretical support for regulating the electronic properties and easy magnetization axis orientation in MnI3 two-dimensional materials.