High-power coherent beam polarization combination of fiber lasers: progress and prospect [Invited]

Coherent polarization beam combining (CPBC) of fiber lasers has the potential to scale the output total power while simultaneously maintaining good beam quality. In this paper, we will present the very recent technical advance in a single-channel coherently combinable linearly polarized narrow-linewidth fiber amplifier and high-power CPBC system. The noise property of a recently developed near 2 kW fiber amplifier and its feasibility in a CPBC system, CPBC of four 500-W-level fiber amplifiers and two kilowatt fiber amplifiers are demonstrated for the first time, which is also the first result for a 2 kW CPBC system. We have also performed numerical analysis on the performance scaling of CPBC, and deduced handy design guidelines for CPBC of a 64-element high-power system.