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arXiv · 1712.04279

Stochastic dressed wavefunction: a numerically exact solver for bosonic impurity model dynamics within wide time interval

Evgeny A. Polyakov·Alexey N. Rubtsov
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Abstract

In the dynamics of driven impurity models, there is a fundamental asymmetry between the processes of emission and absorption of environment excitations: most of the emitted excitations are rapidly and irreversibly scattered away, and only a small amount of them is reabsorbed back. We propose to use a stochastic simulation of the irreversible quantum emission processes in real-time dynamics, while taking into account the reabsorbed virtual excitations by the bath discretization. The resulting method delivers a fast convergence with respect to the number of bath sites, on a wide time interval, without the sign problem.

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Evgeny A. Polyakov, Alexey N. Rubtsov. 2017-12-12. Stochastic dressed wavefunction: a numerically exact solver for bosonic impurity model dynamics within wide time interval. https://arxiv.org/abs/1712.04279

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