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arXiv:2410.21515 · Physical Review Letters

Cavity Spectroscopy for Strongly Correlated Polaritonic Systems

Lukas Grunwald, Emil Viñas Boström, Mark Kamper Svendsen, Dante Marvin Kennes, Ángel Rubio

Published May 16, 2025• 6 citations
arXivHTMLPDF

Abstract

Embedding materials in optical cavities has emerged as an intriguing perspective for controlling quantum materials, but a key challenge lies in measuring properties of the embedded matter. Here, we propose a framework for probing strongly correlated cavity-embedded materials through direct measurements of cavity photons. We derive general relations between photon and matter observables inside the cavity, and show how these can be measured via the emitted photons. As an example, we demonstrate how the entanglement phase transition of an embedded H_{2} molecule can be accessed by measuring the cavity photon occupation, and showcase how dynamical spin correlation functions can be accessed by measuring dynamical photon correlation functions. Our framework provides an all-optical method to measure static and dynamic properties of cavity-embedded materials.

DOI
10.1103/1lpw-22np

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