Sign Reversal of the Anomalous Hall Effect in Magnetically Doped Topological Insulator Thin Films
ORAL
Abstract
Inducing magnetic orders in a topological insulator (TI) to break its time reversal symmetry has revealed many exotic topological quantum phenomena such as quantum anomalous Hall (QAH) effect. The QAH effect has been experimentally realized in the thin films of Cr- and/or V-doped (Bi,Sb)2Te3. The V-doped Sb2Te3is one of two parent systems for the QAH state. Recently, we fabricated the V-doped Sb2Te3films with varying V doping concentration and systematically studied their magneto-transport properties. We observed the sign reversal of the anomalous Hall (AH) effect in the V- doped Sb2Te3films with increasing the V doping concentration. For low doping level, the sign of the AH effect is negative; When the V doping level reaches ~ 3% of Sb , the AH effect starts to show positive sign, consistent with that of the V-doped QAH samples. The observation of the sign reversal of the AH effect in the V-doped Sb2Te3films opens a new route to understand the interplay between the topological states and magnetism in magnetic doped TI films and facilitates the exploration of the underlying mechanism of the V-doped QAH system.
*This work is supported by the ARO Young Investigator Program Award (W911NF1810198), the U.S. DOE Award # DE-SC0019064 and the Alfred P. Sloan Research Fellowship.
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Presenters
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Yifan Zhao
- Department of Physics, Pennsylvania State University
- Department of Physics, The Pennsylvania State University
- Pennsylvania State University