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arXiv · 2610.21428

Crossovers between Time-Bin and Energy-Time Entanglement in Homodyned Resonance Fluorescence

Abstract

We theoretically investigate photonic entanglement generated by homodyning resonance fluorescence from a two-level emitter with a phase-locked laser field. Under weak excitation, increasing the relative laser-field amplitude produces crossovers from time-bin to energy--time and back to time-bin entanglement. The intermediate energy--time regime occurs near amplitude matching, where destructive interference suppresses the single-photon component, allowing the two-photon contributions to dominate the coincidence signal. We evaluate the resulting photon statistics and first-order coherence and characterize the entanglement through violations of the CHSH Bell inequality in a Franson interferometer. This scheme provides a route to controlling photonic entanglement through linear optics and coherent interference.

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Zi-Qi Zeng, Jian Wang, Bang Wu, Zhiliang Yuan. 2026-10-15. Crossovers between Time-Bin and Energy-Time Entanglement in Homodyned Resonance Fluorescence. https://arxiv.org/abs/2610.21428

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