Sixty-six joules has been extracted from a 22-l active volume, 5-atm laser mixture, in a 180-ns (FWHM) optical pulse. The best efficiency obtained under these conditions was 0.8%, based on the available energy stored in the double Blumlein. For the laser chamber geometry used in this experiment it was essential that the surface track path between the positive high-voltage electrode and any ground be a minimum of 3 times the interelectrode separation. The small-signal gain under these operating conditions was 6.0% cm−1 and the measured absorption at the peak of the gain was 0.4% cm−1. We observe that for both volumetric scaling and pulse length scaling the current rise time is of critical importance.

Substitution of neon for argon as the diluent gas in electron-beam-pumped XeF lasers allows increased optical extraction energies of 2.8 J l−1 and efficiencies of 1.8%. The improved performance in neon diluent is due to a reduction of the optical absorption in the laser medium which occurs at the laser wavelength. This optical absorption is shown to be present when the rare gases along are irradiated.

No abstract

No abstract

Temperature-dependent absorption processes in neon/xenon/NF3 mixtures are reported. In pure neon plasmas there are two types of absorption present; a broad but weak band of absorption is observed, which increases with increasing temperature, and a strong narrow band of absorption is observed around 351 nm. Moderate heating reduces this absorption. Improved performance of the XeF laser at elevated temperature is primarily due to reduced absorption in the laser medium at 351 nm.