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The Kondo effect in quantum dots at high voltage: Universality and scaling

A. Rosch·J. Kroha·P. Wölfle
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Abstract

We examine the properties of a dc-biased quantum dot in the Coulomb blockade regime. For voltages V large compared to the Kondo temperature T_K, the physics is governed by the scales V and gamma, where gamma ~ V/ln^2(V/T_K) is the non-equilibrium decoherence rate induced by the voltage-driven current. Based on scaling arguments, self-consistent perturbation theory and perturbative renormalization group, we argue that due to the large gamma, the system can be described by renormalized perturbation theory for ln(V/T_K) >> 1. However, in certain variants of the Kondo problem, two-channel Kondo physics is induced by a large voltage V.

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A. Rosch, J. Kroha, P. Wölfle. 2001-05-02. The Kondo effect in quantum dots at high voltage: Universality and scaling. https://doi.org/10.1103/physrevlett.87.156802

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