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arXiv · 2509.21569

A Markovian approach to $N$-photon correlations beyond the quantum regression theorem

Mateusz Salamon·Oliver Dudgeon·Ahsan Nazir·Jake Iles-Smith
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Abstract

Multi-photon correlations from quantum emitters coupled to vibrational environments lie beyond the reach of standard tools such as the quantum regression theorem (QRT). Here, we introduce a Markovian framework for computing frequency-resolved $N$-photon correlation functions that overcomes this limitation. Applying our approach to a driven semiconductor quantum dot provides a tractable description of phonon effects on fluorescence beyond the single-photon spectrum. Our method accurately captures the emergence of the phonon sideband, missed by conventional QRT treatments, and reveals rich phonon-induced structure in the filtered two-photon spectrum. Strikingly, we find that photons emitted via the phonon sideband inherit second-order coherence properties of the Mollow triplet.

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Mateusz Salamon, Oliver Dudgeon, Ahsan Nazir, Jake Iles-Smith. 2025-09-25. A Markovian approach to $N$-photon correlations beyond the quantum regression theorem. https://doi.org/10.1103/pgk3-b57l

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