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Andreev scattering and cotunneling between two superconductor-normal metal interfaces : the dirty limit

D. Feinberg
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Abstract

Crossed Andreev reflections and cotunneling occur between two neighbouring superconductor- normal metal or superconducting-ferromagnet interfaces. Previous works assumed a clean BCS superconductor. Here the calculation of the corresponding crossed conductance terms is generalized to a dirty superconductor. The range of the effect is shown to be the coherence length $\tildeξ = \sqrt{\hbar D/Δ}$, instead of the BCS coherence length $ξ_0$. Moreover, in three dimensions, the algebraic prefactor scales as $1/r$ instead of $1/r^2$. The calculation involves the virtual diffusion probability of quasiparticles below the superconducting gap, in the normal and the anomalous channel.

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D. Feinberg. 2003-10-13. Andreev scattering and cotunneling between two superconductor-normal metal interfaces : the dirty limit. https://doi.org/10.1140/epjb%2Fe2003-00361-6

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