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arXiv · 0801.2293

The Keldysh action of a multi-terminal time-dependent scatterer

I. Snyman·Y. V. Nazarov
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Abstract

We present a derivation of the Keldysh action of a general multi-channel time-dependent scatterer in the context of the Landauer-Büttiker approach. The action is a convenient building block in the theory of quantum transport. This action is shown to take a compact form that only involves the scattering matrix and reservoir Green functions. We derive two special cases of the general result, one valid when reservoirs are characterized by well-defined filling factors, the other when the scatterer connects two reservoirs. We illustrate its use by considering Full Counting Statistics and the Fermi Edge Singularity.

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I. Snyman, Y. V. Nazarov. 2008-01-15. The Keldysh action of a multi-terminal time-dependent scatterer. https://doi.org/10.1103/physrevb.77.165118

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