Low-temperature surface conduction in the Kondo insulator SmB6

  title={Low-temperature surface conduction in the Kondo insulator SmB6},
  author={Steven Wolgast and Çağlıyan Kurdak and Kai Sun and J. W. Allen and Dae-Jeong Kim and Zachary Fisk},
  journal={Physical Review B},
We study the transport properties of the Kondo insulator SmB6 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 SmB6, to be strong evidence for the topological insulator metallic surface states… 

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