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arXiv · 1111.5805

Unconventional superconductivity in CuxBi2Se3

T. Kirzhner·E. Lahoud·K. B. Chaska·Z. Salman·A. Kanigel
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Abstract

We report point contact measurements in high quality single crystals of Cu0.2Bi2Se3. We observe three different kinds of spectra: (1) Andreev-reflection spectra, from which we infer a superconducting gap size of 0.6mV; (2) spectra with a large gap which closes above Tc at about 10K; and (3) tunneling-like spectra with zero-bias conductance peaks. These tunneling spectra show a very large gap of ~2meV (2Delta/KTc ~ 14).

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T. Kirzhner, E. Lahoud, K. B. Chaska, Z. Salman, A. Kanigel. 2011-11-24. Unconventional superconductivity in CuxBi2Se3. https://doi.org/10.1103/physrevb.86.064517

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