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arXiv · 2609.04171

Twin-photon generation in a silicon nitride microresonator

Franz Pacher·Haochen Yan·Alekhya Ghosh·Arghadeep Pal·Toby Bi·Hao Zhang·Lixing You·Hao Li·Daniela Salvoni·Shuangyou Zhang·Pascal Del'Haye
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Abstract

Photonic chips with silicon nitride ($\mathrm{Si_3N_4}$) microring resonators are well established as heralded single-photon sources, but their operation as frequency-degenerate twin-photon sources has not previously been demonstrated. Here, we realise a twin-photon source at telecommunication wavelengths in a $\mathrm{Si_3N_4}$ ring microresonator via an inverse four-wave mixing (FWM) process, in which two photons from spectrally distinct pumps are converted into a pair of identical twin photons. The measurements show a maximum coincidence-to-accidental ratio (CAR) of $5.4\pm0.6$. In addition, the microresonator functions as a heralded single-photon source through pump-degenerate spontaneous four-wave mixing (SFWM), exhibiting a spectral purity of $P=0.67\pm0.05$ and a heralded anti-bunching of $g^{(2)}_h(0)=0.0042\pm0.0015$. Together, these results demonstrate both photon-generation schemes on a single integrated $\mathrm{Si_3N_4}$ platform, highlighting its potential for scalable, tailored quantum light generation.

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Franz Pacher, Haochen Yan, Alekhya Ghosh, Arghadeep Pal, Toby Bi, Hao Zhang, Lixing You, Hao Li, Daniela Salvoni, Shuangyou Zhang, Pascal Del'Haye. 2026-09-03. Twin-photon generation in a silicon nitride microresonator. https://arxiv.org/abs/2609.04171

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