12.8-μm NH3 laser emission with 40–60% power conversion and up to 28% energy conversion efficiency

The characteristics of an extremely efficient 12.8-μm NH3 laser utilizing a rather simple and versatile optical pumping arrangement are reported. CO2 laser pump to NH3 laser energy conversion efficiencies of up to 28%, very close to the theoretical limit of 33% for this system, and power conversion efficiencies of 40–60% have been achieved. Both the efficiencies are considerably higher than the best reported to date for this emission.