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arXiv · 2212.03011

Cavity Light-Matter Entanglement through Quantum Fluctuations

Giacomo Passetti·Christian J. Eckhardt·Michael A. Sentef·Dante M. Kennes
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Abstract

The hybridization between light and matter forms the basis to achieve cavity control over quantum materials. In this work we investigate a cavity coupled to an XXZ quantum chain of interacting spinless fermions by numerically exact solutions and perturbative analytical expansions. We find two important effects: (i) Specific quantum fluctuations of the matter system play a pivotal role in achieving entanglement between light and matter; and (ii) in turn, light-matter entanglement is the key ingredient to modify electronic properties by the cavity. We hypothesize that quantum fluctuations of those matter operators to which the cavity modes couple are a general prerequisite for light-matter entanglement in the groundstate. Implications of our findings for light-matter-entangled phases, cavity-modified phase transitions in correlated systems, and measurement of light-matter entanglement through Kubo response functions are discussed.

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Giacomo Passetti, Christian J. Eckhardt, Michael A. Sentef, Dante M. Kennes. 2022-12-06. Cavity Light-Matter Entanglement through Quantum Fluctuations. https://doi.org/10.1103/physrevlett.131.023601

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