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arXiv · 1511.00109

Time-dependent Landauer-Büttiker formalism for superconducting junctions at arbitrary temperatures

Riku Tuovinen·Robert van Leeuwen·Enrico Perfetto·Gianluca Stefanucci
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Abstract

We discuss an extension of our earlier work on the time-dependent Landauer--Büttiker formalism for noninteracting electronic transport. The formalism can without complication be extended to superconducting central regions since the Green's functions in the Nambu representation satisfy the same equations of motion which, in turn, leads to the same closed expression for the equal-time lesser Green's function, i.e., for the time-dependent reduced one-particle density matrix. We further write the finite-temperature frequency integrals in terms of known special functions thereby considerably speeding up the computation. Numerical simulations in simple normal metal -- superconductor -- normal metal junctions are also presented.

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Riku Tuovinen, Robert van Leeuwen, Enrico Perfetto, Gianluca Stefanucci. 2016-04-14. Time-dependent Landauer-Büttiker formalism for superconducting junctions at arbitrary temperatures. https://doi.org/10.1088/1742-6596%2F696%2F1%2F012016

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