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arXiv · 1502.07794

Disentangling the magnetoelectric and thermoelectric transport in topological insulator thin films

Jinsong Zhang·Xiao Feng·Yong Xu·Minghua Guo·Zuocheng Zhang·Yunbo Ou·Yang Feng·Kang Li·Haijun Zhang·Lili Wang·Xi Chen·Zhongxue Gan·Shou-Cheng Zhang·Ke He·Xucun Ma·Qi-Kun Xue·Yayu Wang
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Abstract

We report transport studies on (Bi,Sb)2Te3 topological insulator thin films with tunable electronic band structure. We find a doping and temperature regime in which the Hall coefficient is negative indicative of electron-type carriers, whereas the Seebeck coefficient is positive indicative of hole-type carriers. This sign anomaly is due to the distinct transport behaviors of the bulk and surface states: the surface Dirac fermions dominate magnetoelectric transport while the thermoelectric effect is mainly determined by the bulk states. These findings may inspire new ideas for designing topological insulator-based high efficiency thermoelectric devices.

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Jinsong Zhang, Xiao Feng, Yong Xu, Minghua Guo, Zuocheng Zhang, Yunbo Ou, Yang Feng, Kang Li, Haijun Zhang, Lili Wang, Xi Chen, Zhongxue Gan, Shou-Cheng Zhang, Ke He, Xucun Ma, Qi-Kun Xue, Yayu Wang. 2015-02-27. Disentangling the magnetoelectric and thermoelectric transport in topological insulator thin films. https://doi.org/10.1103/physrevb.91.075431

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