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arXiv · 0712.3381

Superconducting gap of overdoped Tl2Ba2CuO6+d observed by Raman scattering

K. Nishikawa·T. Masui·S. Tajima·H. Eisaki·H. Kito·A. Iyo
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Abstract

We report Raman scattering spectra for single crystals of overdoped Tl2Ba2CuO6+d (Tl-2201) at low temperatures. It was observed that the pair-breaking peaks in A1g and B1g spectra radically shift to lower energy with carrier doping. We interpret it as s-wave component mixing into d-wave, although the crystal structure is tetragonal. Since similar phenomena were observed also in YBa2Cu3Oy and Bi2Sr2CaCu2Oz, we conclude that s-wave mixing is a common property for overdoped high-Tc superconductors.

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K. Nishikawa, T. Masui, S. Tajima, H. Eisaki, H. Kito, A. Iyo. 2007-12-20. Superconducting gap of overdoped Tl2Ba2CuO6+d observed by Raman scattering. https://doi.org/10.1016/j.jpcs.2008.06.022

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