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arXiv · 1606.08254

Fermiology of possible topological superconductor Tl0.5Bi2Te3 derived from hole-doped topological insulator

C. X. Trang·Z. Wang·D. Takane·K. Nakayama·S. Souma·T. Sato·T. Takahashi·A. A. Taskin·Yoichi Ando
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Abstract

We have performed angle-resolved photoemission spectroscopy on Tl0.5Bi2Te3, a possible topological superconductor derived from Bi2Te3. We found that the bulk Fermi surface consists of multiple three-dimensional hole pockets surrounding the Z point, produced by the direct hole doping into the valence band. The Dirac-cone surface state is well isolated from the bulk bands, and the surface chemical potential is variable in the entire band-gap range. Tl0.5Bi2Te3 thus provides an excellent platform to realize two-dimensional topological superconductivity through a proximity effect from the superconducting bulk. Also, the observed Fermi-surface topology provides a concrete basis for constructing theoretical models for bulk topological superconductivity in hole-doped topological insulators.

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C. X. Trang, Z. Wang, D. Takane, K. Nakayama, S. Souma, T. Sato, T. Takahashi, A. A. Taskin, Yoichi Ando. 2016-06-27. Fermiology of possible topological superconductor Tl0.5Bi2Te3 derived from hole-doped topological insulator. https://doi.org/10.1103/physrevb.93.241103

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