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arXiv · 2512.08650

Perfect continuous-variable quantum microcombs

Kangkang Li·Yue Wang·Ze Wang·Xin Zhou·Jincheng Li·Yinke Cheng·Binyan Wu·Qihuang Gong·Bei-Bei Li·Qi-Fan Yang
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Abstract

Quantum microcombs generated in high-Q microresonators provide compact, multiplexed sources of entangled modes for continuous-variable (CV) quantum information processing. While deterministic generation of CV states via Kerr-induced two-mode squeezing has been demonstrated, achieving spectrally uniform squeezing remains challenging because of asymmetry and anomalies in the dispersion profile. Here we overcome these limitations by combining a microresonator with an engineered mode spectrum and optimized pump conditions. We realize a CV quantum microcomb comprising 14 independent two-mode squeezed states, each exhibiting more than 4 dB of raw squeezing (up to 4.3 dB) across a 0.7 THz bandwidth. This uniform, high-performance quantum resource represents a key step toward scalable, integrated CV quantum technologies operating beyond classical limits.

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Kangkang Li, Yue Wang, Ze Wang, Xin Zhou, Jincheng Li, Yinke Cheng, Binyan Wu, Qihuang Gong, Bei-Bei Li, Qi-Fan Yang. 2025-12-09. Perfect continuous-variable quantum microcombs. https://arxiv.org/abs/2512.08650

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