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arXiv · 2111.06408

Phase Transitions in the Classical Simulability of Open Quantum Systems

F. Azad·A. Hallam·J. Morley·A. G. Green
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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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F. Azad, A. Hallam, J. Morley, A. G. Green. 2021-11-11. Phase Transitions in the Classical Simulability of Open Quantum Systems. https://arxiv.org/abs/2111.06408

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