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Real-time dynamics in Quantum Impurity Systems: A Time-dependent Numerical Renormalization Group Approach

Frithjof B. Anders·Avraham Schiller
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Abstract

We develop a general approach to the nonequilibrium dynamics of quantum impurity systems for arbitrary coupling strength. The numerical renormalization group is used to generate a complete basis set necessary for the correct description of the time evolution. We benchmark our method with the exact analytical solution for the resonant-level model. As a first application, we investigate the equilibration of a quantum dot subject to a sudden change of the gate voltage and external magnetic field. Two distinct relaxation times are identified for the spin and charge dynamics.

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Frithjof B. Anders, Avraham Schiller. 2005-05-23. Real-time dynamics in Quantum Impurity Systems: A Time-dependent Numerical Renormalization Group Approach. https://doi.org/10.1103/physrevlett.95.196801

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