Quantum critical behavior influenced by measurement backaction in ultracold gases

  title={Quantum critical behavior influenced by measurement backaction in ultracold gases},
  author={Yuto Ashida and Shunsuke Furukawa and Masahito Ueda},
  journal={Physical Review A},
Recent realizations of quantum gas microscope offer the possibility of continuous monitoring of the dynamics of a quantum many-body system at the single-particle level. By analyzing effective non-Hermitian Hamiltonians of interacting bosons in an optical lattice and continuum, we demonstrate that the backaction of quantum measurement shifts the quantum critical point and gives rise to a unique critical phase beyond the terrain of the standard universality class. We perform mean-field and strong… 

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