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arXiv · 1211.5104

Low-temperature surface conduction in the Kondo insulator SmB$_6$

Steven Wolgast·Cagliyan Kurdak·Kai Sun·J. W. Allen·Dae-Jeong Kim·Zachary Fisk
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Abstract

We study the transport properties of the Kondo insulator SmB$_6$ with a specialized configuration designed to distinguish bulk-dominated conduction from surface-dominated conduction. We find that as the material is cooled below 4 K, it exhibits a crossover from bulk to surface conduction with a fully insulating bulk. We take the robustness and magnitude of the surface conductivity, as is manifest in the literature of SmB$_6$, to be strong evidence for the topological insulator metallic surface states recently predicted for this material.

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Steven Wolgast, Cagliyan Kurdak, Kai Sun, J. W. Allen, Dae-Jeong Kim, Zachary Fisk. 2013-12-02. Low-temperature surface conduction in the Kondo insulator SmB$_6$. https://doi.org/10.1103/physrevb.88.180405

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