Theoretical Design of Robust Ferromagnetism and Bipolar Semiconductivity in Graphene-Based Nanoroads

Abstract

The search for graphene-based materials for spintronics applications has intensified in recent years, and numerous designs have been proposed based on various modifications to pristine graphene. Despite the tremendous progress made in the past, finding a design that can be realized in practice remains a challenging task. Encouraged by recent experimental breakthroughs, here we propose a feasible scheme to realize graphene-based magnetic nanoroads. This new material consists of a half-hydrogenated graphene nanoroad embedded in a fully hydrogenated graphene sheet. Using first-principles density functional theory calculations, we demonstrate that such a design can convert nonmagnetic pristine graphene into a bipolar ferromagnetic semiconductor. More importantly, as a result of areal magnetization enabled by half-hydrogenation, the overall magnetism of such a nanoroad is very robust against a variation of either its width or orientation. We also propose a simple design of an all-electric controlled device bas...