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arXiv · 1412.5449

Heavy surface state in a possible topological Kondo insulator: Magneto-thermoelectric transport on the (011)-plane of SmB$_6$

Yongkang Luo·Hua Chen·Jianhui Dai·Zhu-an Xu·J. D. Thompson
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Abstract

Motivated by the high sensitivity to Fermi surface topology and scattering mechanisms in magneto-thermoelectric transport, we have measured the thermopower and Nernst effect on the (011)-plane of the proposed topological Kondo insulator SmB$_6$. These experiments, together with electrical resistivity and Hall effect measurements, demonstrate that the (011)-plane also harbors a metallic surface with the effective mass in the order of 10-10$^2$ $m_0$. The surface and bulk conductances are well distinguished in these measurements and are categorized into metallic and non-degenerate semiconducting regimes, respectively. Electronic correlations play an important role in enhancing scattering and also contribute to the heavy surface state.

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Yongkang Luo, Hua Chen, Jianhui Dai, Zhu-an Xu, J. D. Thompson. 2014-12-17. Heavy surface state in a possible topological Kondo insulator: Magneto-thermoelectric transport on the (011)-plane of SmB$_6$. https://doi.org/10.1103/physrevb.91.075130

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