Kinetic processes in continuously pulsed copper halide lasers

Absorption measurements in the afterglow of electrically excited copper halide laser mixtures are described. Ground state and metastable copper density decay rates determine the optimum delay for application of a second electrical pulse. Output energy densities of 45 μJ . cm-3have been observed for single-pulse conditions. Gas temperature increases limit the electrical pulse energy which can be applied on a continuous basis, and in this regime the output energy density is reduced to~ 11 . cm-3due to the decreased pulse energy and cumulative population effects. Thermal gradients and radial cataphoresis are suggested as explanations for observed transient effects in the multipulse output envelope. Average 5106 Å power levels of 1.34 W at 0.3 percent efficiency were observed within 18 kHz burst-mode pulses applied at low duty cycle.