Free-fermion Page curve: Canonical typicality and dynamical emergence

  title={Free-fermion Page curve: Canonical typicality and dynamical emergence},
  author={Xie-hang Yu and Zongping Gong and Juan Ignacio Cirac},
  journal={Physical Review Research},
We provide further analytical insights into the newly established noninteracting (free-fermion) Page curve, focusing on both the kinematic and dynamical aspects. First, we unveil the underlying canonical typicality and atypicality for random free-fermion states. The former appears for a small subsystem and is exponentially weaker than the well-known result in the interacting case. The latter explains why the free-fermion Page curve differs remarkably from the interacting one when the subsystem… 
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