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arXiv · cond-mat/9811195

Multiple Andreev reflections as a transport problem in energy space

G. Johansson·K. N. Bratus'·V. S. Shumeiko·G. Wendin
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Abstract

We present an approach for analyzing the dc current in voltage biased quantum superconducting junctions. By separating terms from different $n$-particle processes, we find that the $n$-particle current can be mapped on the problem of wave transport through a potential structure with $n$ barriers. We discuss the relation between resonances in such structures and the subgap structures in the current-voltage characteristics. At zero temperature we find, exactly, that only processes creating real excitations contribute to the current. Our results are valid for a general SXS-junction, where the X-region is an arbitrary non-superconducting region described by an energy-dependent transfer matrix.

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G. Johansson, K. N. Bratus', V. S. Shumeiko, G. Wendin. 1998-11-13. Multiple Andreev reflections as a transport problem in energy space. https://doi.org/10.1006/spmi.1999.0740

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