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Cooper pair delocalization in disordered media

M. A. N. Araujo·M. Dzierzawa·C. Aebischer·D. Baeriswyl
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Abstract

We discuss the effect of disorder on the coherent propagation of the bound state of two attracting particles. It is shown that a result analogous to the Anderson theorem for dirty superconductors is also valid for the Cooper problem, namely, that the pair wave function is extended beyond the single-particle localization length if the latter is large. A physical justification is given in terms of the Thouless block-scaling picture of localization. These arguments are supplemented by numerical simulations. With increasing disorder we find a transition from a regime in which the interaction delocalizes the pair to a regime in which the interaction enhances localization.

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M. A. N. Araujo, M. Dzierzawa, C. Aebischer, D. Baeriswyl. 1997-08-04. Cooper pair delocalization in disordered media. https://doi.org/10.1016/s0921-4526(97)00454-7

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