Reversible control of Dzyaloshinskii-Moriya interaction at the graphene/Co interface via hydrogen absorption
Baishun Yang, Qirui Cui, Jinghua Liang, Mairbek Chshiev, Hongxin Yang
Abstract
Using first-principles calculations, we investigate the impact of hydrogenation on the Dzyaloshinskii-Moriya interaction (DMI) at graphene/Co interface. We find that both the magnitude and chirality of DMI can be controlled via hydrogenation absorbed on graphene surface. Our analysis using density of states combined with first-order perturbation theory reveals that the spin splitting and the occupation of Co-$d$ orbitals, especially the ${d}_{xz}$ and ${d}_{{z}^{2}}$ states, play a crucial role in defining the magnitude and the chirality of DMI. Moreover, we find that the DMI oscillates with a period of two atomic layers as a function of Co thickness what could be explained by analysis of out-of-plane of Co orbitals. Our work elucidates the underlying mechanisms of interfacial DMI origin and provides an alternative route of its control for spintronic applications.