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Crossover from Non-Equilibrium to Equilibrium Behavior in the Time-Dependent Kondo Model

D. Lobaskin·S. Kehrein
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Abstract

We investigate the equilibration of a Kondo model that is initially prepared in a non-equilibrium state towards its equilibrium behavior. Such initial non-equilibrium states can e.g. be realized in quantum dot experiments with time-dependent gate voltages. We evaluate the non-equilibrium spin-spin correlation function at the Toulouse point of the Kondo model exactly and analyze the crossover between non-equilibrium and equilibrium behavior as the non-equilibrium initial state evolves as a function of the waiting time for the first spin measurement. Using the flow equation method we extend these results to the experimentally relevant limit of small Kondo couplings.

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D. Lobaskin, S. Kehrein. 2004-08-20. Crossover from Non-Equilibrium to Equilibrium Behavior in the Time-Dependent Kondo Model. https://doi.org/10.1103/physrevb.71.193303

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