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Insulating state of granular superconductors in a strong-coupling regime

I. S. Beloborodov·Ya. V. Fominov·A. V. Lopatin·V. M. Vinokur
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Abstract

We analyze the possibility of the formation of a magnetic-field-induced insulating state in a two-dimensional granular superconductor with relatively strong intergranular coupling and show that such a state appears in a model with spatial variations of the single-grain critical magnetic field. This model describes realistic granular samples with the dispersion in grain sizes and explains the mechanism leading to a giant peak in the magnetoresistance.

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I. S. Beloborodov, Ya. V. Fominov, A. V. Lopatin, V. M. Vinokur. 2006-07-12. Insulating state of granular superconductors in a strong-coupling regime. https://doi.org/10.1103/physrevb.74.014502

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