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arXiv · 0907.1125

Quantum oscillations in a topological insulator Bi_{1-x}Sb_{x}

A. A. Taskin·Yoichi Ando
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Abstract

We have studied transport and magnetic properties of Bi_{1-x}Sb_x, which is believed to be a topological insulator - a new state of matter where an insulating bulk supports an intrinsically metallic surface. In nominally insulating Bi_{0.91}Sb_{0.09} crystals, we observed strong quantum oscillations of the magnetization and the resistivity originating from a Fermi surface which has a clear two-dimensional character. In addition, a three-dimensional Fermi surface is found to coexist, which is possibly due to an unusual coupling of the bulk to the surface. This finding demonstrates that quantum oscillations can be a powerful tool to directly probe the novel electronic states in topological insulators.

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A. A. Taskin, Yoichi Ando. 2009-07-07. Quantum oscillations in a topological insulator Bi_{1-x}Sb_{x}. https://doi.org/10.1103/physrevb.80.085303

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