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arXiv · 2510.23572

FPGA-Based Adaptive Control for Phase Stabilization in Fiber-Optic Interferometers Using Correlated Photons

P. M. Berto·F. CampodÓnico·A. A. Matoso·S. Vergara·P. A. Coelho·G. Lima·S. PÁdua·J. CariÑe
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Abstract

Time-bin encoded photon pairs enable robust, decoherence-resistant transmission through optical fibers for long-distance quantum communication, where phase noise poses a critical limitation to stable operation. Here, we implement an adaptive Perturbation-and-Observe algorithm on a fully digital FPGA platform operating with real-time feedback at 1 Hz. The control signal is derived from the coincidence counts of correlated photon pairs. This adaptive approach reduces the rise time by 70\% and the coincidence noise by 30\%, resulting in visibility improvements sustained for more than 600 s.These results provide an efficient solution for long-term phase stabilization in quantum and photonic systems.

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P. M. Berto, F. CampodÓnico, A. A. Matoso, S. Vergara, P. A. Coelho, G. Lima, S. PÁdua, J. CariÑe. 2025-10-27. FPGA-Based Adaptive Control for Phase Stabilization in Fiber-Optic Interferometers Using Correlated Photons. https://arxiv.org/abs/2510.23572

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