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arXiv · 1112.0102

Superconductivity in the doped topological insulator Cu$_x$Bi$_2$Se$_3$ under high pressure

T. V. Bay·T. Naka·Y. K. Huang·H. Luigjes·M. S. Golden·A. de Visser
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Abstract

We report a high-pressure single crystal study of the topological superconductor Cu$_x$Bi$_2$Se$_3$. Resistivity measurements under pressure show superconductivity is depressed smoothly. At the same time the metallic behavior is gradually lost. The upper critical field data $B_{c2}(T)$ under pressure collapse onto a universal curve. The absence of Pauli limiting and the comparison of $B_{c2}(T)$ to a polar state function point to spin-triplet superconductivity, but an anisotropic spin-singlet state cannot be discarded completely.

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T. V. Bay, T. Naka, Y. K. Huang, H. Luigjes, M. S. Golden, A. de Visser. 2011-12-01. Superconductivity in the doped topological insulator Cu$_x$Bi$_2$Se$_3$ under high pressure. https://doi.org/10.1103/physrevlett.108.057001

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