Chinese Optics Letters

A fast-tunable and stable fiber microcavity for coupling Ba+ ions in quantum networks

Fang Ding, Chenghao Zhang, Weibin Chen, Jin‐Ming Cui, Yunfeng Huang, Chuan‐Feng Li, Guang-Can Guo

Published Jan 1, 2025• 2 citations

Abstract

We present the design, implementation, and characterization of a high-stability, fast-tunable fiber Fabry-Pérot microcavity system optimized for coupling with Ba + ions to form quantum network nodes.The microcavity system integrates multiwavelength single-mode transmission, rapid and broad-band tunability, high finesse, and exceptional passive mechanical stability.By incorporating a unique vibration isolation structure, the system enables the fiber-optic microcavity (with a finesse of 8000) to remain resonant with the laser for several minutes even without active feedback.Furthermore, we demonstrate active cavity length stabilization using the Pound-Drever-Hall method, which significantly suppresses low-frequency vibrations and enables the cavity length to remain stable for several days.Experimental results show that this fiber microcavity system offers outstanding stability and flexibility for practical quantum network applications, providing reliable technical support for the construction of large-scale quantum networks based on trapped ions.

DOI: 10.3788/col202523.120201

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