Characteristics of a linearly pumped laser oscillator-amplifier at 496 μm

A linearly pumped methyl fluoride laser oscillator-amplifier is described which yields a peak power of 30 kW in a linewidth <60 MHz. Linear pumping results in nearly complete saturation of the FIR transition and consequently in relatively high photon conversion efficiency, which in the present case is 70% of its maximum theoretical value at operating pressures of 2-3 Torr. The present result indicates that MW-level peak power, such as required for plasma-ion scattering experiments, may be achieved using less than 140 MW of CO₂ laser pumping power (<14 J in 100 nsec) in an amplifier less than 2 m long.