Weak Ergodicity Breaking and Quantum Many-Body Scars in Spin-1 XY Magnets.

  title={Weak Ergodicity Breaking and Quantum Many-Body Scars in Spin-1 XY Magnets.},
  author={Michael Schecter and Thomas Iadecola},
  journal={Physical review letters},
  volume={123 14},
We study the spin-1 XY model on a hypercubic lattice in d dimensions and show that this well-known nonintegrable model hosts an extensive set of anomalous finite-energy-density eigenstates with remarkable properties. Namely, they exhibit subextensive entanglement entropy and spatiotemporal long-range order, both believed to be impossible in typical highly excited eigenstates of nonintegrable quantum many-body systems. While generic initial states are expected to thermalize, we show analytically… 

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