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arXiv · 1003.1713

Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit

J. G. Analytis·R. D. McDonald·S. C. Riggs·J. -H. Chu·G. S. Boebinger·I. R. Fisher
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Abstract

Pulsed magnetic fields of up to 55T are used to investigate the transport properties of the topological insulator Bi_2Se_3 in the extreme quantum limit. For samples with a bulk carrier density of n = 2.9\times10^16cm^-3, the lowest Landau level of the bulk 3D Fermi surface is reached by a field of 4T. For fields well beyond this limit, Shubnikov-de Haas oscillations arising from quantization of the 2D surface state are observed, with the ν=1 Landau level attained by a field of 35T. These measurements reveal the presence of additional oscillations which occur at fields corresponding to simple rational fractions of the integer Landau indices.

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J. G. Analytis, R. D. McDonald, S. C. Riggs, J. -H. Chu, G. S. Boebinger, I. R. Fisher. 2010-03-08. Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit. https://doi.org/10.1038/nphys1861

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