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arXiv · 2004.01133

Numerical evaluation of two-time correlation functions in open quantum systems with matrix product state methods: a comparison

Stefan Wolff·Ameneh Sheikhan·Corinna Kollath
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Abstract

We compare the efficiency of different matrix product state (MPS) based methods for the calculation of two-time correlation functions in open quantum systems. The methods are the purification approach [1] and two approaches [2,3] based on the Monte-Carlo wave function (MCWF) sampling of stochastic quantum trajectories using MPS techniques. We consider a XXZ spin chain either exposed to dephasing noise or to a dissipative local spin flip. We find that the preference for one of the approaches in terms of numerical efficiency depends strongly on the specific form of dissipation.

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Stefan Wolff, Ameneh Sheikhan, Corinna Kollath. 2020-04-02. Numerical evaluation of two-time correlation functions in open quantum systems with matrix product state methods: a comparison. https://arxiv.org/abs/2004.01133

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