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arXiv · 1108.1887

Electrochemical synthesis and superconducting phase diagram of Cu_xBi2Se3

M. Kriener·Kouji Segawa·Zhi Ren·Satoshi Sasaki·Shohei Wada·Susumu Kuwabata·Yoichi Ando
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Abstract

The superconducting Cu_xBi_2Se_3 is an electron-doped topological insulator and is a prime candidate of the topological superconductor which still awaits discovery. The electrochemical intercalation technique for synthesizing Cu_xBi2Se3 offers good control of restricting Cu into the van-der-Waals gap and yields samples with shielding fractions of up to ~50%. We report essential details of this synthesis technique and present the established superconducting phase diagram of T_c vs x, along with a diagram of the shielding fraction vs x. Intriguingly, those diagrams suggest that there is a tendency to spontaneously form small islands of optimum superconductor in this material.

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M. Kriener, Kouji Segawa, Zhi Ren, Satoshi Sasaki, Shohei Wada, Susumu Kuwabata, Yoichi Ando. 2011-08-09. Electrochemical synthesis and superconducting phase diagram of Cu_xBi2Se3. https://doi.org/10.1103/physrevb.84.054513

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