Single-mode narrow-bandwidth temporally shaped nanosecond-pulse ytterbium-doped fiber MOPA for a large-scale laser facility front-end

We present a fiber master oscillator power amplifier system designed to meet stringent requirements of large-scale laser facility front-end sources. A strictly single-mode beam without spatial phase, narrow-bandwidth nanosecond pulse amplification up to 20 mu J is obtained with more than 40 dB optical signal-to-noise ratio, 30 dB polarization extinction ratio, and sub-nanosecond resolution temporal shaping. Experimental results are in excellent agreement with numerical simulations including amplified spontaneous emission. Such a system could advantageously replace cumbersome bulky solid systems. (C) 2010 Optical Society of America