Phase Transitions in the Classical Simulability of Open Quantum Systems

• URL: http://arxiv.org/abs/2111.06408v1
• Date: Thu, 11 Nov 2021 19:00:00 GMT
• Title: Phase Transitions in the Classical Simulability of Open Quantum Systems
• Authors: F. Azad, A. Hallam, J. Morley, A. G. Green
• Abstract summary: We study the evolution of an open quantum system using a Langevin unravelling of the density matrix evolution over matrix product states. As the strength of coupling to and temperature of the environment is increased, we find a transition where the entanglement of the individual trajectories saturates, permitting a classical simulation of the system for all times.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: We study the evolution of an open quantum system using a Langevin unravelling of the density matrix evolution over matrix product states. As the strength of coupling to and temperature of the environment is increased, we find a transition where the entanglement of the individual trajectories saturates, permitting a classical simulation of the system for all times. This is the Hamiltonian open system counterpart of the saturation in entanglement found in random circuits with projective or weak measurements. If a system is open, there is a limit to the advantage in simulating its behaviour on a quantum computer, even when that evolution harbours important quantum effects.

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