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arXiv · 1011.2846

Large bulk resistivity and surface quantum oscillations in the topological insulator Bi2Te2Se

Zhi Ren·A. A. Taskin·Satoshi Sasaki·Kouji Segawa·Yoichi Ando
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Abstract

Topological insulators are predicted to present novel surface transport phenomena, but their experimental studies have been hindered by a metallic bulk conduction that overwhelms the surface transport. We show that a new topological insulator, Bi2Te2Se, presents a high resistivity exceeding 1 Ohm-cm and a variable-range hopping behavior, and yet presents Shubnikov-de Haas oscillations coming from the surface Dirac fermions. Furthermore, we have been able to clarify both the bulk and surface transport channels, establishing a comprehensive understanding of the transport in this material. Our results demonstrate that Bi2Te2Se is the best material to date for studying the surface quantum transport in a topological insulator.

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Zhi Ren, A. A. Taskin, Satoshi Sasaki, Kouji Segawa, Yoichi Ando. 2010-11-12. Large bulk resistivity and surface quantum oscillations in the topological insulator Bi2Te2Se. https://doi.org/10.1103/physrevb.82.241306

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