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arXiv · 1111.1485

Landau quantization and the thickness limit of topological insulator thin films of Sb2Te3

Yeping Jiang·Yilin Wang·Mu Chen·Zhi Li·Canli Song·Ke He·Lili Wang·Xi Chen·Xucun Ma·Qi-Kun Xue
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Abstract

We report the experimental observation of Landau quantization of molecular beam epitaxy grown Sb2Te3 thin films by a low-temperature scanning tunneling microscope. Different from all the reported systems, the Landau quantization in Sb2Te3 topological insulator is not sensitive to the intrinsic substitutional defects in the films. As a result, a nearly perfect linear energy dispersion of surface states as 2D massless Dirac fermion system is achieved. We demonstrate that 4 quintuple layers are the thickness limit for Sb2Te3 thin film being a 3D topological insulator. The mechanism of the Landau level broadening is discussed in terms of enhanced quasiparticle lifetime.

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Yeping Jiang, Yilin Wang, Mu Chen, Zhi Li, Canli Song, Ke He, Lili Wang, Xi Chen, Xucun Ma, Qi-Kun Xue. 2011-11-07. Landau quantization and the thickness limit of topological insulator thin films of Sb2Te3. https://doi.org/10.1103/physrevlett.108.016401

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