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arXiv · 0910.2844

AC-Conductance through an Interacting Quantum Dot

Björn Kubala·Florian Marquardt
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Abstract

We investigate the linear ac-conductance for tunneling through an arbitrary interacting quantum dot in the presence of a finite dc-bias. In analogy to the well-known Meir-Wingreen formula for the dc case, we are able to derive a general formula for the ac-conductance. It can be expressed entirely in terms of local correlations on the quantum dot, in the form of a Keldysh block diagram with four external legs. We illustrate the use of this formula as a starting point for diagrammatic calculations by considering the ac-conductance of the noninteracting resonant level model and deriving the result for the lowest order of electron-phonon coupling. We show how known results are recovered in the appropriate limits.

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Björn Kubala, Florian Marquardt. 2009-10-15. AC-Conductance through an Interacting Quantum Dot. https://doi.org/10.1103/physrevb.81.115319

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