Multi-Wavelength Soliton-Based Probing and Quantum-Ready Fiber Monitoring

The increasing deployment of short-haul optical fibers in data centers and metropolitaninfrastructures has created a growing need for continuous, scalable, and physics-basedmonitoring solutions. Conventional optical time-domain reflectometry (OTDR) techniquesface limitations in short fiber links due to dense reflections, multipath interference, andrestricted dynamic range, while emerging security concerns demand sensitivity to subtle,non-destructive perturbations.This work proposes a multi-wavelength probing architecture based on externally generatedsoliton microcombs for parallel fiber monitoring. In contrast to traditionalsingle-wavelength OTDR systems, the proposed approach employs a shared, chip-scalesoliton comb source to generate a dense set of mutually coherent probe wavelengths thatpropagate linearly through existing fiber infrastructure. These wavelengths act asindependent sensing channels, enabling simultaneous interrogation of multiple fibers ormultiple spectral views of a single link.The paper focuses on system architecture, physical feasibility, and monitoring capabilitiesrather than quantum state generation or protocol design. Particular attention is given tocompatibility with emerging quantum communication infrastructure, where physical-layerintegrity and timing stability are critical prerequisites. By decoupling soliton generationfrom the monitored fiber and leveraging established fiber propagation physics, theproposed framework provides a realistic path toward scalable, quantum-ready fibermonitoring without modifications to deployed optical networks.