Nuclear Physics B

Universal entanglement of mid-spectrum eigenstates of chaotic local Hamiltonians

Yichen Huang

Published Mar 10, 2021• 27 citations

Abstract

In systems governed by chaotic local Hamiltonians, my previous work [7] conjectured the universality of the average entanglement entropy of all eigenstates by proposing an exact formula for its dependence on the subsystem size. In this note, I extend this result to the average entanglement entropy of a constant fraction of eigenstates in the middle of the energy spectrum. The generalized formula is supported by numerical simulations of various chaotic spin chains.

DOI: 10.1016/j.nuclphysb.2021.115373

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