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arXiv · 0708.2516

Superconductor-insulator transition in Coulomb disorder

B. I. Shklovskii
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Abstract

Superconductor-insulator transition driven by the decreasing concentration of electrons $n$ is studied in the case of the disorder potential created by randomly positioned charged impurities. Electrons and Cooper pairs (formed by an non-Coulomb attraction) nonlinearly screen the random potential of impurities. Both electrons and Cooper pairs can be delocalized or localized in the resulting self-consistent potential. The border separating the superconductor and insulator phases in the plane of the concentration of electrons and the length of the Cooper pair is found. For a strong disorder the central segment of this border follows the BEC-BCS crossover line defined for a clean sample.

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B. I. Shklovskii. 2007-11-05. Superconductor-insulator transition in Coulomb disorder. https://doi.org/10.1103/physrevb.76.224511

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