FPGA-based residual amplitude modulation suppression and control for compact atomic clocks

2023/11/01 by Tin Nghia Nguyen, Nguyen, Tin Nghia, T. R. Schibli +1
Physics and Astronomy · #Advanced Frequency and Time Standards #Atomic Physics (physics.atom-ph) #Atomic and Subatomic Physics Research #FOS: Physical sciences #Quantum optics and atomic interactions

paper · pdf · doi:10.48550/arxiv.2311.00216

openalex publication_date 2023/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We designed an FPGA fabric to provide phase modulation techniques to lock lasers to optical frequency references. The method incorporates an active residual-amplitude-modulation (RAM) suppression scheme that relies on complex modulation. All the required servos to construct an optical atomic clock are incorporated onto the same low-cost, commercial FPGA chip. We demonstrate a reliable, long-term RAM suppression 60 dB with the remaining RAM level at -100 dBc and an improved stability of three decades when applied on a two-photon rubidium clock.

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