Insulating state of granular superconductors in a strong-coupling regime
نویسندگان
چکیده
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 a dispersion in grain sizes and explains the mechanism leading to a giant peak in the magnetoresistance.
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