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Scaling and Decoherence in the Out-of-Equilibrium Kondo Model

Stefan Kehrein
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Abstract

We study the Kondo effect in quantum dots in an out-of-equilibrium state due to an applied dc-voltage bias. Using the method of infinitesimal unitary transformations (flow equations), we develop a perturbative scaling picture that naturally contains both equilibrium coherent and non-equilibrium decoherence effects. This framework allows one to study the competition between Kondo effect and current-induced decoherence, and it establishes a large regime dominated by single-channel Kondo physics for asymmetrically coupled quantum dots.

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Stefan Kehrein. 2004-10-26. Scaling and Decoherence in the Out-of-Equilibrium Kondo Model. https://doi.org/10.1103/physrevlett.95.056602

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