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arXiv · 1005.1672

Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects

Zhenhua Qiao·Shengyuan A. Yang·Wanxiang Feng·Wang-Kong Tse·Jun Ding·Yugui Yao·Jian Wang·Qian Niu
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Abstract

We investigate the possibility of realizing quantum anomalous Hall effect in graphene. We show that a bulk energy gap can be opened in the presence of both Rashba spin-orbit coupling and an exchange field. We calculate the Berry curvature distribution and find a non-zero Chern number for the valence bands and demonstrate the existence of gapless edge states. Inspired by this finding, we also study, by first principles method, a concrete example of graphene with Fe atoms adsorbed on top, obtaining the same result.

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Zhenhua Qiao, Shengyuan A. Yang, Wanxiang Feng, Wang-Kong Tse, Jun Ding, Yugui Yao, Jian Wang, Qian Niu. 2010-09-10. Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects. https://doi.org/10.1103/physrevb.82.161414

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