LAUSR

Abstract Coherently combining of seven-channel narrow-linewidth, linear-polarized, kW-level power all-fiber amplifiers has been successfully demonstrated by using the stochastic parallel gradient descent (SPGD) algorithm. The seven polarization-maintained fiber amplifiers are tiled by a collimator array with a high lenslet filling factor (~95%). Total emitting power is ~8 kW, and ~7.1 kW combined output power is achieved and the contrast of the far-field intensity pattern is measured to be ~86% when the system is in the closed loop. This work could provide practical reference on scaling the output power of the tiled aperture coherent beam combining system.