Electrically tunable quantum anomalous Hall effect in graphene decorated by $5d$ transition-metal adatoms

Based on first-principles calculations, we predict that $5d$ transition-metals on graphene present a unique class of hybrid systems exhibiting topological transport effects that can be manipulated effectively by external electric fields [1]. The origin of this phenomenon lies in the exceptional magnetic properties and the large spin-orbit interaction of the $5d$ metals leading to significant magnetic moments accompanied with colossal magnetocrystalline anisotropy energies. A strong magneto-electric response is predicted that offers the possibility to switch the spontaneous magnetization direction by moderate electric fields, enabling an electrically tunable quantum anomalous Hall effect.\\[4pt] [1] preprint: http://arxiv.org/abs/1108.5915