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arXiv · 2602.21373

Fiber Link Stabilization with a Multicore Fiber Amplifier

Yifan Liu·Takuma Nakamura·Daniel J. Elson·Yuta Wakayama·Charles A. McLemore·Tetsuya Hayashi·Mikael Mazur·Nicolas Fontaine·Franklyn Quinlan·Nazanin Hoghooghi
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Abstract

We study the use of separate cores of a multicore erbium-doped fiber amplifier (MC-EDFA) in a noise-canceled link for ultrastable optical frequency transfer. We demonstrate fractional frequency instability of $5\times10^{-19}$ at 1000 s averaging time for the stabilized MC-EDFA alone and $1.4\times10^{-18}$ at 1000 s averaging time when integrated with a 40 km-long 7-core spooled fiber. This study further establishes multicore fiber (MCF) networks as a promising platform for ultrastable frequency transfer, serving as an important step toward incorporating precision time and frequency distribution into future MCF communication infrastructures.

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Yifan Liu, Takuma Nakamura, Daniel J. Elson, Yuta Wakayama, Charles A. McLemore, Tetsuya Hayashi, Mikael Mazur, Nicolas Fontaine, Franklyn Quinlan, Nazanin Hoghooghi. 2026-02-24. Fiber Link Stabilization with a Multicore Fiber Amplifier. https://arxiv.org/abs/2602.21373

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