ASE and parasitic oscillation assessment in the High Energy pulsed operation of large area diode pumped ceramic slab lasers

DPSSLs are the leading technology for several high energy pulsed applications needing a simple and tough design along with a high "wall-plug" efficiency. Among others, interesting applications include space-born instrumentation, laser x-ray or electron generation, or inertial fusion ignition. Recently we adopted the large area zig-zag ceramic slab scheme as baseline for the amplifier of a Diode Pumped Solid State ns-pulsed MOPA laser system for space applications. Our experience shows that ASE and Parasitic Oscillations are the enemies to face adopting this format. ASE clamped gain measurements and possible countermeasures are reviewed in this paper.