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arXiv · 1011.1281

Scaling approach for the time-dependent Kondo model

C. Tomaras·S. Kehrein
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Abstract

We present a new nonperturbative method to deal with the time-dependent quantum many-body problem, which is an extension of Wegner's flow equations to time-dependent Hamiltonians. The formalism provides a scaling procedure for the set of time-dependent interaction constants. We apply these ideas to a Kondo model with a ferromagnetic exchange coupling switched on over a time scale $τ$. We show that the asymptotic expectation value of the impurity spin interpolates continuously between its quenched and adiabatic value.

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C. Tomaras, S. Kehrein. 2010-11-04. Scaling approach for the time-dependent Kondo model. https://doi.org/10.1209/0295-5075%2F93%2F47011

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