Multiple Andreev reflections in diffusive SINIS and SIFIS junctions

A. V. Polkin; P. A. Ioselevich

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arXiv · 2209.07343

Multiple Andreev reflections in diffusive SINIS and SIFIS junctions

A. V. Polkin·P. A. Ioselevich

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Abstract

We study Multiple Andreev Reflections in long diffusive superconductor(S)-normal metal(N)-superconductor junctions with low-transparency interfaces. Assuming strong thermalization in the weak link we calculate the current-voltage dependence $I(V)$. At intermediate temperatures, $E_\mathrm{Th}\ll T\ll\Delta$, the current is dominated by noncoherent multiple Andreev reflections and is obtained analytically. The results are generalized to a ferromagnetic junction. We find that the exchange field produces a non-trivial splitting of the subharmonic gap structure. This effect relies on thermalization and vanishes in SFS junctions with no energy relaxation in the weak link.

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A. V. Polkin, P. A. Ioselevich. 2022-09-15. Multiple Andreev reflections in diffusive SINIS and SIFIS junctions. https://arxiv.org/abs/2209.07343

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