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arXiv · 2608.13091

Time-resolved correlation engineering in DLCZ Raman photon sources

Jiun-Shiuan Shiu·Chang-Wei Lin·Chi-Ming Yang·Ite A. Yu·Yong-Fan Chen
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Abstract

Memory-assisted quantum networks require photon sources with controllable temporal and correlation properties. The Duan-Lukin-Cirac-Zoller (DLCZ) protocol provides a platform based on spontaneous Raman scattering in atomic ensembles, but a unified predictive theory connecting control parameters to correlations under realistic propagation and noise conditions remains lacking. Here we present a propagation-inclusive open-system quantum theory that retains write-induced population redistribution while combining Heisenberg-Langevin dynamics with Maxwell-Schr\"odinger propagation. We experimentally validate its key predictions. The theory predicts time-dependent Stokes generation, spin-wave evolution, retrieved anti-Stokes wavepackets, and time-resolved cross-correlations. Experiments confirm robust correlations under retrieval tuning and enhanced correlations for shorter write pulses, consistent with the different scaling of correlated coincidences and accidental backgrounds with the mean spin-wave excitation number. Classically controlled retrieval enables temporal gating and slicing of the anti-Stokes wavepacket, establishing a quantitative framework for correlation engineering in memory-compatible DLCZ photon sources.

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Jiun-Shiuan Shiu, Chang-Wei Lin, Chi-Ming Yang, Ite A. Yu, Yong-Fan Chen. 2026-08-13. Time-resolved correlation engineering in DLCZ Raman photon sources. https://arxiv.org/abs/2608.13091

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