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Superconductors with Mesoscopic Phase Separation

A. J. Coleman·E. P. Yukalova·V. I. Yukalov
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Abstract

A model of superconductivity is proposed taking into account repulsive particle interaction, mesoscopic phase separation and softening of crystalline lattice. These features are typical of many high-temperature superconductors. The main results obtained for the model are: (i) phase separation is possible only if repulsive forces play a significant role; (ii) the critical temperature as a function of the superconducting phase fraction can have non-monotonic behaviour; (iii) superconductivity is possible in heterophase systems even when it would be forbidden in pure samples. These results are in agreement with experiments.

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A. J. Coleman, E. P. Yukalova, V. I. Yukalov. 1997-11-28. Superconductors with Mesoscopic Phase Separation. https://arxiv.org/abs/cond-mat/9711306

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