Volume Law and Quantum Criticality in the Entanglement Entropy of Excited Eigenstates of the Quantum Ising Model

Lev Vidmar, Lucas Hackl, Eugenio Bianchi, Marcos Rigol

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Much has been learned about universal properties of entanglement entropies in ground states of quantum many-body lattice systems. Here we unveil universal properties of the average bipartite entanglement entropy of eigenstates of the paradigmatic quantum Ising model in one dimension. The leading term exhibits a volume-law scaling that we argue is universal for translationally invariant quadratic models. The subleading term is constant at the critical field for the quantum phase transition and vanishes otherwise (in the thermodynamic limit); i.e., the critical field can be identified from subleading corrections to the average (over all eigenstates) entanglement entropy.

Original languageEnglish (US)
Article number220602
JournalPhysical Review Letters
Issue number22
StatePublished - Nov 28 2018


All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

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