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arXiv · 0810.2900

Density matrix renormalization group study of a quantum impurity model with Landau-Zener time-dependent Hamiltonian

Cheng Guo·Andreas Weichselbaum·Stefan Kehrein·Tao Xiang·Jan von Delft
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Abstract

We use the adaptive time-dependent density matrix renormalization group method (t-DMRG) to study the nonequilibrium dynamics of a benchmark quantum impurity system which has a time-dependent Hamiltonian. This model is a resonant-level model, obtained by a mapping from a certain Ohmic spin-boson model describing the dissipative Landau-Zener transition. We map the resonant-level model onto a Wilson chain, then calculate the time-dependent occupation $n_d(t)$ of the resonant level. We compare t-DMRG results with exact results at zero temperature and find very good agreement. We also give a physical interpretation of the numerical results.

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Cheng Guo, Andreas Weichselbaum, Stefan Kehrein, Tao Xiang, Jan von Delft. 2009-04-01. Density matrix renormalization group study of a quantum impurity model with Landau-Zener time-dependent Hamiltonian. https://doi.org/10.1103/physrevb.79.115137

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