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arXiv · 0904.3455

Crossed Andreev reflection and charge imbalance in diffusive NSN structures

D. S. Golubev·M. S. Kalenkov·A. D. Zaikin
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Abstract

We formulate a microscopic theory of non-local electron transport in three-terminal diffusive normal-superconducting-normal (NSN) structures with arbitrary interface transmissions. At low energies $\varepsilon$ we predict strong enhancement of non-local spectral conductance $g_{12} \propto 1/\varepsilon$ due to quantum interference of electrons in disordered N-terminals. In contrast, non-local resistance $R_{12}$ remains smooth at small $\varepsilon$ and, furthermore, is found to depend neither on parameters of NS interfaces nor on those of N-terminals. At higher temperatures $R_{12}$ exhibits a peak caused by the trade-off between charge imbalance and Andreev reflection. Our results are in a good agreement with recent experimental observations and can be used for quantitative analysis of future experiments.

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D. S. Golubev, M. S. Kalenkov, A. D. Zaikin. 2009-04-22. Crossed Andreev reflection and charge imbalance in diffusive NSN structures. https://doi.org/10.1103/physrevlett.103.067006

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