Tunability of magnetic anisotropy of Co on two-dimensional materials by tetrahedral bonding

Abstract

Pairing of π electronic state structures with functional or metallic atoms makes them possible to engineer physical and chemical properties. Herein, we predict the reorientation of magnetization of Co on hexagonal BN (h-BN) and graphene multilayers. The driving mechanism is the formation of the tetrahedral bonding between sp3 and d orbitals at the interface. More specifically, the intrinsic π bonding of h-BN and graphene is transformed to sp3 as a result of strong hybridization with metallic dz2 orbital. The different features of these two tetrahedral bondings, sp2 and sp3, are well manifested in charge density and density of states in the vicinity of the interface, along with associated band structure near the K̄ valley. Our findings provide an approach to tailoring magnetism by means of degree of the interlayer hybrid bonds in two-dimensional layered materials.