Role of electron filling in the magnetic anisotropy of monolayer WSe2 doped with 5d transition metals

Abstract

Exploring magnetic anisotropy (MA) in single-atom-doped two-dimensional materials provides a viable ground for realizing information storage and processing at ultimate length scales. Herein, the MA of $5d$ transition-metal doped monolayer ${\mathrm{WSe}}_{2}$ is investigated by first-principles calculations. Large MA energy (MAE) is achieved in several doping systems. The direction of MA is determined by the dopant in-plane $d$ states in the vicinity of the Fermi level in line with previous studies. An occupation rule that the parity of the occupation number of the in-plane $d$ orbital of the dopant determines the preference between in-plane and out-of-plane anisotropy is found in this $5d$-doped system. Furthermore, this rule is understood by second-order perturbation theory and proved by charge-doping analysis. Considering relatively little research on two-dimensional MA and not sufficiently large MAE, suitable contact medium dopant pairs with large MAE and tunable MA pave the way to novel data storage paradigms.