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arXiv · 2508.08599

Squeezed Light Generation in Periodically Poled Thin-Film Lithium Niobate Waveguides

Xiaodong Shi·Angela Anna Baiju·Xu Chen·Sakthi Sanjeev Mohanraj·Sihao Wang·Veerendra Dhyani·Biveen Shajilal·Mengyao Zhao·Ran Yang·Yue Li·Guangxing Wu·Hao Hao·Victor Leong·Ping Koy Lam·Di Zhu
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Abstract

Squeezed states of light play a key role in quantum-enhanced sensing and continuous-variable quantum information processing. Realizing integrated squeezed light sources is crucial for developing compact and scalable photonic quantum systems. In this work, we demonstrate on-chip broadband vacuum squeezing at telecommunication wavelengths on the thin-film lithium niobate (TFLN) platform. Our device integrates periodically poled lithium niobate (PPLN) nanophotonic waveguides with low-loss edge couplers, comprising bilayer inverse tapers and an SU-8 polymer waveguide. This configuration achieves a fiber-to-chip coupling loss of 1.4 dB and a total homodyne detection loss of 4 dB, enabling a measured squeezing level of 1.4 dB. Additional measurements in a more efficient PPLN waveguide (without low-loss couplers) infer an on-chip squeezing level of over 10 dB at a pump power of 62 mW. These results underscore the potential of TFLN platform for efficient and scalable squeezed light generation.

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Xiaodong Shi, Angela Anna Baiju, Xu Chen, Sakthi Sanjeev Mohanraj, Sihao Wang, Veerendra Dhyani, Biveen Shajilal, Mengyao Zhao, Ran Yang, Yue Li, Guangxing Wu, Hao Hao, Victor Leong, Ping Koy Lam, Di Zhu. 2025-08-12. Squeezed Light Generation in Periodically Poled Thin-Film Lithium Niobate Waveguides. https://arxiv.org/abs/2508.08599

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