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arXiv · 2602.11752

Broadband Tunable Photon-Pair Generation and Spectrum Measurement Based on Noncritical Lithium Niobate Crystals

Zhao-Qi-Zhi Han·Bo-Wen Liu·He Zhang·Zhi-You Li·Xiao-Hua Wang·Jin-Peng Li·Zheng-He Zhou·Qi-Yu Chen·Yin-Hai Li·Zhi-Yuan Zhou·Bao-Sen Shi
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Abstract

Photon pairs play a vital role in modern science, driving extensive research into their generation. Yet, the narrow phase-matching bandwidth of conventional crystals has largely confined studies to specific wavelengths, leaving research on broadband tunable sources underexplored. Here, we employ a non-critical phase-matched lithium niobate (LN) crystal to generate widely tunable photon pairs. The generated near-infrared (NIR) photon pairs exhibit a high coincidence-to-accidental ratio (CAR > 20 dB) and are tunable across the 800-1600 nm range. We further showcase the utility of NIR photon pairs in spectroscopy by detecting carbon monoxide (CO) gas absorption. This approach will facilitate the design of advanced LN-based photonic experiments.

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Zhao-Qi-Zhi Han, Bo-Wen Liu, He Zhang, Zhi-You Li, Xiao-Hua Wang, Jin-Peng Li, Zheng-He Zhou, Qi-Yu Chen, Yin-Hai Li, Zhi-Yuan Zhou, Bao-Sen Shi. 2026-02-12. Broadband Tunable Photon-Pair Generation and Spectrum Measurement Based on Noncritical Lithium Niobate Crystals. https://arxiv.org/abs/2602.11752

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