Out-of-plane ferromagnetism in two-dimensional 1T-RhO2

초록

Using the combined theoretical approaches, the structural, electronic, and magnetic properties of the two-dimensional (2D) 1T phase of monolayer RhO2 were studied. Density-functional theory plus U calculation indicate that 1T -RhO2 favors a ferromagnetic metallic phase with an out-of-plane magnetization, and it can be achieved by exfoliation from the layered bulk oxides containing monolayer 1T-RhO2. Monte Carlo simulation shows that the ferromagnetic phase is stable below the Curie temperature of 73.9 K based on the Heisenberg Hamiltonian model. Magnetic anisotropy energy and its cause were further investigated to understand the microscopic origin of the 2D magnetization. Our results indicate that spin-orbit coupling interaction between Rh 4d stabilizes perpendicular magnetic anisotropy, resulting in the out-of-plane magnetization, over in-plane magnetic anisotropy. In addition, mechanical tensile strain can strengthen perpendicular magnetic anisotropy by increasing positive contribution of the interaction to the magnetic anisotropy energy.

키워드