An 8.2 J solid-state laser using phase-conjugation to coherently combine eight parallel amplifiers

Coherent coupling, or beam combining, offers a significant benefit to designers of practical high-power lasers. Unlimited by volume availability, the medium selection trade-offs can be based on many other important material parameters including stimulated-emission cross section and saturation fluence, compatibility with diode pumping, available optical quality, resistance to radiation damage, and thermo-mechanical properties. In our flashlamp-pumped laser, we chose Cr-sensitized, Nd-doped gadolinium scandium gallium garnet (Cr:Nd:GSGG), which is significantly more efficient than Nd:YAG and has thermo-mechanical properties that are vastly superior to those of Nd:glass.<>