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arXiv · 1103.2966

Correlation between T_c and the Cu 4s level reveals the mechanism of high-temperature superconductivity

Z. D. Dimitrov·S. K. Varbev·K. J. Omar·A. A. Stefanov·E. S. Penev·T. M. Mishonov
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Abstract

Band structure trends in hole-doped cuprates and correlations with T_c are interpreted within the s--d exchange mechanism of high-T_c superconductivity. The dependence of T_c on the position of the copper 4s level finds a natural explanation in the generic Cu 3d, Cu 4s, O 2p_x and O 2p_y four-band model. The Cu 3d--Cu 4s intra-atomic exchange interaction is incorporated in the standard BCS scheme. This dependence of T_c in the whole interval of 25--125 K has no alternative explanation at present, and possibly this quarter of a century standing puzzle is already solved.

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Z. D. Dimitrov, S. K. Varbev, K. J. Omar, A. A. Stefanov, E. S. Penev, T. M. Mishonov. 2011-05-12. Correlation between T_c and the Cu 4s level reveals the mechanism of high-temperature superconductivity. https://arxiv.org/abs/1103.2966

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