Newtype two-dimensional Cr2O3 monolayer with half-metallicity, high curie temperature, and magnetic anisotropy

Abstract

Due to 100% spin polarization, half-metallic systems play a great role in the development of nanoscale spintronic devices. We conduct extensive calculations within spin-polarized density functional theory to design a newtpye two-dimensional Cr2O3 monolayer. The monolayer demonstrates robust stability as verified by formation energy, phonon spectrum, elastic constants, and molecular dynamics simulation. Each Cr2O3 unit cell gives rise to a total magnetic moment of 6.0 μB, mainly resulting from Cr sites due to the cooperation between crystal-field effect and Hund’s exchange. The monolayer is identified as a half-metallic ferromagnet with Curie temperature up to 460 K and 100% spin polarization. The super-exchange mechanism and direct exchange interaction are responsible for the ferromagnetic coupling. Moreover, the system shows large magnetic anisotropy with the easy axis in the basal plane. The excellent stability, half-metallicity, high Curie temperature, and magnetic anisotropy endow the monolayer with great potential in spintronic devices. This work provides a new pathway for designing ferromagnetic material with half-metallicity and high Curie temperature.