TIME-RESOLVED MEASUREMENTS OF EXCITED-STATE DENSITIES IN A COPPER VAPOR LASER

Time-resolved measurements of copper and neon buffer gas excited state densities in a copper vapor laser (CVL) during the excitation pulse and early afterglow are reported for both optimum and nonoptimum power input conditions. The optimum condition results demonstrate that the termination of the laser pulse in the CVL is due not only to filling of the lower laser level, but also a reduction in the upper laser level pumping related to the collapse of power input to the plasma during the excitation pulse. Time-resolved measurements of excited state densities over a wide range of input power conditions clearly illustrate that the increase in copper density with power input reduces the peak electron temperature in the plasma during the excitation pulse. This reduction in peak electron temperature is important in limiting the scaling of CVL output power with input power-copper density. Finally, good agreement between the experimental results and the predictions of the computer modeling of Kushner [5] with regard to energy partitioning among excited states is demonstrated. © 1990 IEEE