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Impact of Coulomb interaction and Kondo effect on transport in quantum dots

A. Golub
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Abstract

We examine the impact of Coulomb electron-electron interaction on transport in a junction with a quantum dot described by Kondo Hamiltonian. We analyze the Fermi liquid regime and consider the limit of zero temperature. With the help of Keldysh technique we calculate the non-linear current and shot noise as a function of applied voltage. We show that Coulomb interaction markable influences the universal effective charge of current-carrying particles e*=5/3e which can be measured in shot-noise experiments. The electron-electron interaction modifies this universal value by a factor (e*=5/3eF) which is less then one and also voltage dependent.

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A. Golub. 2006-11-21. Impact of Coulomb interaction and Kondo effect on transport in quantum dots. https://doi.org/10.1063/1.2759720

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