2026/08/05 by Francesca Famà, Stefano Dello Russo, Stefano Giaccari +14
Physics and Astronomy · #quant-ph
15 pages main text. The file contains also 10pages of supplementary material
arxiv created 2026/08/05 · arxiv updated 2026/08/06
High-Q silicon nitride microresonators are versatile sources for generating photon pairs via four-wave mixing. We investigate the spectral coherence of this process, tracking the transition from the spontaneous quantum regime to the onset of optical parametric oscillation. By combining time-correlation measurements with phase-sensitive measurements, we continuously monitor the emission linewidth as it evolves from a cavity-lifetime-limited linewidth toward the pump-linewidth scale. This characterization is essential for optimizing integrated sources for scalable quantum networks.