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arXiv · 1206.2186

Hybrid NRG-DMRG approach to real-time dynamics of quantum impurity systems

Fabian Guettge·Frithjof B. Anders·Ulrich Schollwoeck·Eitan Eidelstein·Avraham Schiller
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Abstract

A hybrid approach to nonequilibrium dynamics of quantum impurity systems is presented. The numerical renormalization group serves as a means to generate a suitable low-energy Hamiltonian, allowing for an accurate evaluation of the real-time dynamics of the problem up to exponentially long times using primarily the time-adaptive density-matrix renormalization group. We extract the decay time of the interaction-enhanced oscillations in the interacting resonant-level model and show their quadratic divergence with the interaction strength U. Our numerical analysis is in excellent agreement with analytic predictions based on an expansion in 1/U.

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Fabian Guettge, Frithjof B. Anders, Ulrich Schollwoeck, Eitan Eidelstein, Avraham Schiller. 2012-06-11. Hybrid NRG-DMRG approach to real-time dynamics of quantum impurity systems. https://doi.org/10.1103/physrevb.87.115115

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