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arXiv:2407.12083 · Physical Review Letters

Entanglement Structure of Non-Gaussian States and How to Measure It

Henry Froland, Torsten V. Zache, R.J. Ott, Niklas Mueller

Published Jun 9, 2025• 1 citation
arXivHTMLPDF

Abstract

Rapidly growing capabilities of quantum simulators to probe quantum many-body phenomena require new methods to characterize increasingly complex states. We present a protocol that constrains quantum states using experimentally measured correlation functions. This method enables measurement of a quantum state's entanglement structure, opening a new route to study entanglement-related phenomena. Our approach extends Gaussian state parameterizations by systematically incorporating higher-order correlations. We show the protocol's usefulness in conjunction with current and forthcoming experimental capabilities, focusing on weakly interacting fermions as a proof of concept. Here, the lowest nontrivial expansion quantitatively predicts early time thermalization dynamics, including signaling the onset of quantum chaos indicated by the entanglement Hamiltonian.

DOI
10.1103/pnp2-g1g5

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