Pressure-induced superconductivity in topological parent compound Bi₂Te

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 108; no. 1; pp. 24 - 28
• Main Authors: Zhang, J.L, Zhang, S.J, Weng, H.M, Zhang, W, Yang, L.X, Liu, Q.Q, Feng, S.M, Wang, X.C, Yu, R.C, Cao, L.Z, Wang, L, Yang, W.G, Liu, H.Z, Zhao, W.Y, Zhang, S.C, Dai, X, Fang, Z, Jin, C.Q
• Format: Journal Article
• Language: English
• Published: National Academy of Sciences 2011
• ISSN: 0027-8424; 1091-6490

We report a successful observation of pressure-induced superconductivity in a topological compound Bi₂Te₃ with Tc of ~3 K between 3 to 6 GPa. The combined high-pressure structure investigations with synchrotron radiation indicated that the superconductivity occurred at the ambient phase without crystal structure phase transition. The Hall effects measurements indicated the hole-type carrier in the pressure-induced superconducting Bi₂Te₃ single crystal. Consequently, the first-principles calculations based on the structural data obtained by the Rietveld refinement of X-ray diffraction patterns at high pressure showed that the electronic structure under pressure remained topologically nontrivial. The results suggested that topological superconductivity can be realized in Bi₂Te₃ due to the proximity effect between superconducting bulk states and Dirac-type surface states. We also discuss the possibility that the bulk state could be a topological superconductor.