Coherent polarization beam combining of fiber lasers to 2 kW power-level

Four channels of 500 W power-level all fiberized, narrow-band, and polarization-maintained amplifiers are coaxially combined using active phasing coherent polarization beam combining (CPBC) system. When the phase control system is in closed loop, 2164 W output power is achieved with combing efficiency of 94.5%. In the experiment, the combining efficiency does not degrade obviously along with power scaling process. This is the highest output power based on CPBC system up to now.