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arXiv · 1509.06608

Field-effect Modulation of Anomalous Hall Effect in Diluted Ferromagnetic Topological Insulator Epitaxial Films

Cui-Zu Chang·Min-Hao Liu·Zuo-Cheng Zhang·Yayu Wang·Ke He·Qi-Kun Xue
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Abstract

High quality chromium (Cr) doped three-dimensional topological insulator (TI) Sb2Te3 films are grown via molecular beam epitaxy on heat-treated insulating SrTiO3(111) substrates. We report that the Dirac surface states are insensitive to Cr doping, and a perfect robust long-range ferromagnetic order is unveiled in epitaxial Sb2-xCrxTe3 films. The anomalous Hall effect is modulated by applying a bottom gate, contrary to the ferromagnetism in conventional diluted magnetic semiconductors (DMSs), here the coercivity field is not significantly changed with decreasing carrier density. Carrier-independent ferromagnetism heralds Sb2-xCrxTe3 films as the base candidate TI material to realize the quantum anomalous Hall (QAH) effect. These results also indicate the potential of controlling anomalous Hall voltage in future TI-based magneto-electronics and spintronics.

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Cui-Zu Chang, Min-Hao Liu, Zuo-Cheng Zhang, Yayu Wang, Ke He, Qi-Kun Xue. 2015-09-22. Field-effect Modulation of Anomalous Hall Effect in Diluted Ferromagnetic Topological Insulator Epitaxial Films. https://doi.org/10.1007/s11433-015-5761-9

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