Narrow-linewidth high power fiber laser with output power of 334 W in all-fiber MOPA format

A narrow-linewidth high power Yb-doped fiber laser in all-fiber format is set up. The seed laser has an output power of more than 40 mW with linewidth narrower than 100 MHz. The fiber laser employs three-stage master oscillator power amplifier(MOPA) configuration. It outputs 334 W narrow-linewidth laser when pumped with a total power of 405 W in the main amplifier. The optical-to-optical conversion efficiency is 82.4%. Presently, the output power is limited by the pump power. It can be predicted that the laser power can be further scaled with increased available pump power.