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arXiv · 2008.12782

Entanglement of midspectrum eigenstates of chaotic many-body systems: Reasons for deviation from random ensembles

Masudul Haque·Paul A. McClarty·Ivan M. Khaymovich
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Abstract

Eigenstates of local many-body interacting systems that are far from spectral edges are thought to be ergodic and close to being random states. This is consistent with the eigenstate thermalization hypothesis and volume-law scaling of entanglement. We point out that systematic departures from complete randomness are generically present in mid-spectrum eigenstates, and focus on the departure of the entanglement entropy from the random-state prediction. We show that the departure is (partly) due to spatial correlations and due to orthogonality to the eigenstates at the spectral edge, which imposes structure on the mid-spectrum eigenstates.

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BibTeXRIS

Masudul Haque, Paul A. McClarty, Ivan M. Khaymovich. 2020-08-28. Entanglement of midspectrum eigenstates of chaotic many-body systems: Reasons for deviation from random ensembles. https://doi.org/10.1103/physreve.105.014109

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