DESIGN AND OPERATION OF A 150-W NEAR DIFFRACTION-LIMITED LASER-AMPLIFIER WITH SBS WAVE-FRONT CORRECTION

The design and operation of a Nd:glass regenerative amplifier using a stimulated Brillouin scattering (SBS) phase conjugate mirror is presen ted. The system can be operated at 25-30 J per pulse with a pulse widt h of 14 ns and a pulse repetition frequency (PRF) of 6 Hz. This result s in an average output power of > 150 W with a peak power of 2 GW. The experimentally measured divergence of the amplifier output is 1.25 x the diffraction limit and it can be frequency doubled with > 80% effic iency. The detailed considerations required for this specific amplifie r design are discussed as well as how these considerations apply to th e design of high average power, high beam quality laser systems in gen eral.