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arXiv · 1305.3766

Mass acquisition of Dirac fermions in Cr-doped topological insulator Sb2Te3 films

Yeping Jiang·Zhi Li·Canli Song·Mu Chen·Richard L. Greene·Ke He·Lili Wang·Xi Chen·Xucun Ma·Qi-Kun Xue
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Abstract

We introduce time-reversal-symmetry breaking by doping Cr atoms into the topmost quintuple layer or into the bulk of Sb2Te3 thin films. We find that even at a high Cr-doping level the Landau level spectrum keeps a good quality, enabling the first demonstration of deviation of the zero-mode Landau level, induced by the acquisition of a mass term in the surface states in the presence of surface or bulk magnetic doping. The magnitude of the mass term in the surface states increases with increasing Cr-doping level. Our observation suggests Cr-doped Sb2Te3 is a promising candidate for the realization of the proposed novel magnetoelectric effects.

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Yeping Jiang, Zhi Li, Canli Song, Mu Chen, Richard L. Greene, Ke He, Lili Wang, Xi Chen, Xucun Ma, Qi-Kun Xue. 2013-05-16. Mass acquisition of Dirac fermions in Cr-doped topological insulator Sb2Te3 films. https://doi.org/10.1103/physrevb.92.195418

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