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arXiv · 0904.1829

Large Gap Topological Insulator Bi2Te3 with a Single Dirac Cone on the Surface

Y. L. Chen·J. G. Analytis·J. H. Chu·Z. K. Liu·S. K. Mo·X. L. Qi·H. J. Zhang·D. H. Lu·X. Dai·Z. Fang·S. C. Zhang·I. R. Fisher·Z. Hussain·Z. X. Shen
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Abstract

We investigate the surface state of Bi$_2$Te$_3$ using angle resolved photoemission spectroscopy (ARPES) and transport measurements. By scanning over the entire Brillouin zone (BZ), we demonstrate that the surface state consists of a single non-degenerate Dirac cone centered at the $Γ$ point. Furthermore, with appropriate hole (Sn) doping to counteract intrinsic n-type doping from vacancy and anti-site defects, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states, consistent with a carrier sign change near this doping in transport properties. Our experimental results establish for the first time that Bi$_2$Te$_3$ is a three dimensional topological insulator with a single Dirac cone on the surface, as predicted by a recent theory.

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Y. L. Chen, J. G. Analytis, J. H. Chu, Z. K. Liu, S. K. Mo, X. L. Qi, H. J. Zhang, D. H. Lu, X. Dai, Z. Fang, S. C. Zhang, I. R. Fisher, Z. Hussain, Z. X. Shen. 2009-04-12. Large Gap Topological Insulator Bi2Te3 with a Single Dirac Cone on the Surface. https://arxiv.org/abs/0904.1829

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