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arXiv:2508.11311

Quantum-Enhanced Sensing of Excited-State Dynamics with Correlated Photons

Jiahao Fan, Feihong Liu, Dangyuan Lei, Zhedong Zhang

Published Aug 15, 2025• 0 citations
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Abstract

The squeezed photons, as a quantum-correlated light with reduced noise, have emerged as a great resource for sensing the structures of matter. Here we study the transient absorption (TA) scheme using the squeezed photons whose spectral correlation of amplitudes can be tailored. A microscopic theory is developed, revealing a highly time-energy-resolved nature of the signal that is not attainable by conventional TA scheme. Such a capability is elaborated by applying to monolayer transition metal dichalcogenide materials (TMDs), achieving a real-time monitoring of valley excitons and their dynamics. Moreover, we show the intermediate squeezing regime-not the strong squeezing-which the time-resolved spectroscopy is in favor of. Our work offers a new paradigm for studying nonequilibrium dynamics of matter, in light of the photocatalysis and optoelectronics.

DOI
10.48550/arxiv.2508.11311

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