Stimulated Brillouin Scattering Suppression in Fiber Amplifiers via Chirped Diode Lasers

摘要

We propose to simultaneously suppress stimulated Brillouin scattering (SBS) and enable coherent combination by seeding fiber amplifiers with a linearly-chirped diode laser. The seed spectrum will appear broadband to suppress the SBS, but the well-defined chirp will have sufficient coherence to allow the active phasing of multiple amplifiers. The phasing can be accomplished without strict optical path-length matching by interfering each amplifier's output with a reference, processing the resulting signal with a phase-locked loop, and using the error signal to drive an acousto-optic frequency shifter at the frontend of each fiber amplifier.