Dynamical Purification Phase Transition Induced by Quantum Measurements

@article{Gullans2020DynamicalPP,
  title={Dynamical Purification Phase Transition Induced by Quantum Measurements},
  author={Michael J. Gullans and David A. Huse},
  journal={Physical Review X},
  year={2020}
}
Continuously monitoring the environment of a quantum many-body system reduces the entropy of (purifies) the reduced density matrix of the system, conditional on the outcomes of the measurements. We show that, for mixed initial states, a balanced competition between measurements and entangling interactions within the system can result in a dynamical purification phase transition between (i) a phase that locally purifies at a constant system-size-independent rate, and (ii) a "mixed" phase where… 

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