  We have developed a Watt-level random laser at 532 nm. The laser is based on
a 1064 nm random distributed ytterbium-gain assisted fiber laser seed with a
0.35 nm line-width 900mW polarized output power. A study for the optimal length
of the random distributed mirror was carried out. An ytterbium-doped fiber
master oscillator power amplifier architecture is used to amplify the random
seeder laser without additional spectral broadening up to 20 W. By using a
periodically poled lithium niobate (PPLN) crystal in a single pass
configuration we generate in excess of 1 W random laser at 532 nm by second
harmonic generation with an efficiency of 9 %. The green random laser exhibits
an instability <1 %, optical signal to noise ratio >70 dB, 0.1 nm linewidth and
excellent beam quality.
