Variation of pulse width in copper vapor lasers

It is pointed out that many characteristics of pulsed metal vapor lasers are not well understood at the present time. One of the most puzzling is the variability in laser pulse width found in different laboratories. Pulse widths as wide as 185 nsec and as short as 5 nsec have been observed in copper vapor. A description is provided of the results of a study of the parameters controlling this output pulse width. Operation both without mirrors (superfluorescent or superluminescent mode) and with mirrors (laser mode) is considered. The principal parameters minimizing pulse width are found to include large buffer pressure, large discharge voltage, small discharge capacitance, small discharge circuit inductance, short hot zone length, and optimum discharge tube temperature. The optimum performance obtained for a short pulse laser was a pulse width of 5 nsec and a peak power of 141 kW