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arXiv · 2210.03733

Two-photon emission in detuned resonance fluorescence

Eduardo Zubizarreta Casalengua·Elena del Valle·Fabrice P. Laussy
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Abstract

We discuss two-photon correlations from the side peaks that are formed when a two-level system emitter is driven coherently, with a detuning between the driving source and the emitter (quasi-resonance fluorescence). We do so in the context of the theories of frequency-resolved photon correlations and homodyning, showing that their combination leads to a neat picture compatible with perturbative two-photon scattering that was popular in the early days of quantum electrodynamics. This should help to control, enhance and open new regimes of multiphoton emission. We also propose a way to evidence the quantum coherent nature of the process from photoluminescence only, through the observation of a collapse of the symmetry of the lineshape accompanied by a surge of its intensity of emission. We discuss several of our results in the light of recent experimental works.

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Eduardo Zubizarreta Casalengua, Elena del Valle, Fabrice P. Laussy. 2022-10-18. Two-photon emission in detuned resonance fluorescence. https://doi.org/10.1088/1402-4896%2Facc89e

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