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arXiv · 2605.14777

Programmable cavity-enhanced telecom quantum memory in thin-film lithium niobate

Chengdong Yang·Hanwen Guo·Yu-Yang An·Qian He·Chi Lu·Ziheng Jiang·Yan-Qing Lu·Shining Zhu·Xiao-Song Ma
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Abstract

Spectrally multiplexed telecom quantum networks require quantum memories combining efficient storage with programmable frequency addressing. An integrated implementation should therefore unite a native telecom transition, efficient storage, and fast on-chip spectral control. Here we demonstrate a cavity-enhanced memory in an isotopically purified $^{167}\mathrm{Er}^{3+}$-doped thin-film lithium niobate microring. Long-lived hyperfine shelving states enable persistent, high-contrast atomic frequency comb preparation with a single-component lifetime of $277.6(52.6)$~s, while cavity impedance matching yields $23.3(5)\%$ on-chip efficiency for 100-ns storage. The intrinsic electro-optic response enables frequency-selective storage and routing at rates up to 20~MHz. We further store and retrieve time-energy-entangled telecom photons, violating an entanglement-witness bound by more than 11 standard deviations. Our results establish erbium-doped thin-film lithium niobate as a programmable light--matter interface for spectrally multiplexed quantum networks.

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Chengdong Yang, Hanwen Guo, Yu-Yang An, Qian He, Chi Lu, Ziheng Jiang, Yan-Qing Lu, Shining Zhu, Xiao-Song Ma. 2026-05-14. Programmable cavity-enhanced telecom quantum memory in thin-film lithium niobate. https://arxiv.org/abs/2605.14777

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