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arXiv · 1809.06337

Electronic Fingerprints of Cr and V Dopants in Topological Insulator Sb2Te3

Wenhan Zhang·Damien West·Seng Huat Lee·Yunsheng Qiu·Cui-Zu Chang·Jagadeesh S. Moodera·Yew San Hor·Shengbai Zhang·Weida Wu
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Abstract

By combining scanning tunneling microscopy/spectroscopy and first-principles calculations, we systematically study the local electronic states of magnetic dopants V and Cr in the topological insulator (TI) Sb2Te3. Spectroscopic imaging shows diverse local defect states between Cr and V, which agree with our first-principle calculations. The unique spectroscopic features of V and Cr dopants provide electronic fingerprints for the co-doped magnetic TI samples with the enhanced quantum anomalous Hall effect. Our results also facilitate the exploration of the underlying mechanism of the enhanced quantum anomalous Hall temperature in Cr/V co-doped TIs.

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Wenhan Zhang, Damien West, Seng Huat Lee, Yunsheng Qiu, Cui-Zu Chang, Jagadeesh S. Moodera, Yew San Hor, Shengbai Zhang, Weida Wu. 2018-09-17. Electronic Fingerprints of Cr and V Dopants in Topological Insulator Sb2Te3. https://doi.org/10.1103/physrevb.98.115165

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