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High-order current correlation functions in Kondo systems

A. Golub
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Abstract

We examine the statistics of current fluctuations in a junction with a quantum dot described by Kondo Hamiltonian. With the help of modified Keldish technique we calculate the third current cumulant. As a function of ratio $v=eV/T_{K}$ the 3rd cumulant was obtained for three different regimes: Fermi liquid regime (v<1), crossover interval ($v\geq1$) and RG limit (v>>1). Unlike the case of noninteracting dot, 3rd cumulant shows strong non-linear voltage dependence. Only in the asymptotical limit of large voltages the linear dependence on $V$ is recovered.

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A. Golub. 2004-09-06. High-order current correlation functions in Kondo systems. https://doi.org/10.1103/physrevb.72.075331

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