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Updated: May 6, 2026

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Surface hall effect and nonlocal transport in SmB₆: evidence for surface conduction
11] Dept. of Physics and Astronomy, University of California, Irvine, California 92697, USA [2].
Abstract:
A topological insulator (TI) is an unusual quantum state in which the insulating bulk is topologically distinct from vacuum, resulting in a unique metallic surface that is robust against time-reversal invariant perturbations. The surface transport, however, remains difficult to isolate from the bulk conduction in most existing TI crystals (particularly Bi₂Se₃, Bi₂Te₃ and Sb₂Te₃) due to impurity caused bulk conduction. We report in large crystals of topological Kondo insulator (TKI) candidate material SmB₆ the thickness-independent surface Hall effects and non-local transport, which persist after various surface perturbations. These results serve as proof that at low temperatures SmB₆ has a metallic surface that surrounds an insulating bulk, paving the way for transport studies of the surface state in this proposed TKI material.
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