High peak power narrow-linewidth linearly polarized all-fiber nanosecond laser

Abstract

An all-fiber laser is developed with high peak power, narrow linewidth,linearly polarization, and nanosecond pulse. The single-frequency continuous fiber laser is externally modulated by an electro-optical intensity modulator(EOIM) and a stable pulsed seed laser is obtained with the pulse width of 10 ns and the repetitions rate of 10 kHz. Multistage MOPA structure scheme is adopted.After two stages core-pumped preamplifiers and three stages cladding-pumped amplifiers, the average output power of the laser reach to 21.3W with the peak power of 267 kW. At the highest output power, the signalto-noise ratio of the spectral is greater than 30dB, the polarization extinction ratio is superior 15dB and the Mx2 and My2 factors are 1.28, 1.23, respectively. Stimulated Brillouin scattering (SBS) was not found in the experiment. By increasing the pump power, the average power and peak power can be further improved.