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arXiv · cond-mat/9907483

Spectral Features of the Proximity Effect

S. Pilgram·W. Belzig·C. Bruder
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Abstract

We calculate the local density of states (LDOS) of a superconductor-normal metal sandwich at arbitrary impurity concentration. The presence of the superconductor induces a gap in the normal metal spectrum that is proportional to the inverse of the elastic mean free path $l$ for rather clean systems. For a mean free path much shorter than the thickness of the normal metal, we find a gap size proportional to $l$ that approaches the behavior predicted by the Usadel equation (diffusive limit).

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S. Pilgram, W. Belzig, C. Bruder. 1999-07-30. Spectral Features of the Proximity Effect. https://doi.org/10.1016/s0921-4526(99)01827-x

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