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Tunneling Spectroscopy on c-axis Y{1-x}Ca{x}Ba2Cu3O{7-delta} Thin Films

J. H. Ngai·W. A. Atkinson·J. Y. T. Wei
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Abstract

Scanning tunneling spectroscopy was performed on c-axis Y{1-x}Ca{x}Ba2Cu3O{7-delta} thin films for x= 0, 0.05, 0.15 and 0.20 at 4.2K. The measured spectra show main-gap, sub-gap and satellite features which scale similarly in energy versus Ca-doping, suggesting that they are associated with a single pairing energy. The data is analyzed with a multiband tunneling model which attributes the sub-gap features to the chain band and the satellite and main-gap features to the plane band for d+s pairing symmetry. These results suggest that the superconductivity in Y{1-x}Ca{x}Ba2Cu3O{7-delta} involves multiple bands.

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J. H. Ngai, W. A. Atkinson, J. Y. T. Wei. 2007-03-18. Tunneling Spectroscopy on c-axis Y{1-x}Ca{x}Ba2Cu3O{7-delta} Thin Films. https://doi.org/10.1103/physrevlett.98.177003

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