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arXiv · 2111.12048

Entanglement-Optimal Trajectories of Many-Body Quantum Markov Processes

Tatiana Vovk·Hannes Pichler
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Abstract

We develop a novel approach aimed at solving the equations of motion of open quantum many-body systems. It is based on a combination of generalized wave function trajectories and matrix product states. We introduce an adaptive quantum stochastic propagator, which minimizes the expected entanglement in the many-body quantum state, thus minimizing the computational cost of the matrix product state representation of each trajectory. We illustrate this approach on the example of a one-dimensional open Brownian circuit. We show that this model displays an entanglement phase transition between area and volume law when changing between different propagators and that our method autonomously finds an efficiently representable area law unravelling.

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Tatiana Vovk, Hannes Pichler. 2021-11-23. Entanglement-Optimal Trajectories of Many-Body Quantum Markov Processes. https://doi.org/10.1103/physrevlett.128.243601

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