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arXiv · 1609.07578

Mass-Imbalanced Superconductivity in Effective Two-Channel Kondo Lattice

Hiroaki Kusunose
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Abstract

We propose that mass-imbalanced superconductivity is realized in an effective two-channel Kondo lattice, and its characteristic property appears in electromagnetic responses such as the Meissner effect. Starting from an effective two-channel Kondo lattice model as a low-energy effective theory, and approximating it with two mean-field order parameter components in a self-consistent fashion, it is shown that the balance of the two components is sensitively reflected in the magnitude of the Meissner kernel, while thermodynamic properties are little affected by the balance. This remarkable behavior is understood by the localized character of one partner in the Cooper pair, namely, the effect of the mass imbalance. We briefly mention the relevance to the huge enhancement of the upper critical field under pressure observed in Pr 1-2-20 systems.

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Hiroaki Kusunose. 2016-09-24. Mass-Imbalanced Superconductivity in Effective Two-Channel Kondo Lattice. https://doi.org/10.7566/jpsj.85.113701

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