Loschmidt echo in many-body localized phases

  title={Loschmidt echo in many-body localized phases},
  author={Maksym Serbyn and Dmitry A. Abanin},
  journal={Physical Review B},
The Loschmidt echo, defined as the overlap between quantum wave function evolved with different Hamiltonians, quantifies the sensitivity of quantum dynamics to perturbations and is often used as a probe of quantum chaos. In this work we consider the behavior of the Loschmidt echo in the many-body localized phase, which is characterized by emergent local integrals of motion and provides a generic example of nonergodic dynamics. We demonstrate that the fluctuations of the Loschmidt echo decay as… 

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