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arXiv · 1205.0876

Finite frequency noise properties of the non-equilibrium Anderson impurity model

Christoph P. Orth·Daniel F. Urban·Andreas Komnik
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Abstract

We analyze the spectrum of the electric-current autocorrelation function (noise power) in the Anderson impurity model biased by a finite transport voltage. Special emphasis is placed on the interplay of non-equilibrium effects and electron-electron interactions. Analytic results are presented for a perturbation expansion in the interaction strength $U$. Compared to the non-interacting setup we find a suppression of noise for finite frequencies in equilibrium and an amplification in non-equilibrium. Furthermore, we use a diagrammatic resummation scheme to obtain non-perturbative results in the regime of intermediate $U$. At finite voltage, the noise spectrum shows sharp peaks at positions related to the Kondo temperature instead of the voltage.

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Christoph P. Orth, Daniel F. Urban, Andreas Komnik. 2012-05-04. Finite frequency noise properties of the non-equilibrium Anderson impurity model. https://doi.org/10.1103/physrevb.86.125324

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