Xe2Cl fluorescence and absorption in self-sustained discharge XeCl lasers

Abstract

Fluorescence at 490 nm from the triatomic excimer Xe2Cl* has been investigated to determine the 308 nm absorption due to this species in an x-ray preionized, self-sustained gas discharge XeCl laser. The dependence of Xe2Cl* density on laser intensity (at 308 nm), buffer gas and Xe and HCl partial pressures has been determined for discharges with a peak electrical power deposition of 2.5 GWl−1. Xe2Cl* absorption is estimated to reach 0.6% cm−1 under non-lasing conditions but decreases to a non-saturable 0.2% cm−1 for intracavity laser intensity>1 MW cm−2. XeCl* and Xe2Cl* fluorescence intensities were found to be a similar for both helium and neon buffer gases but laser output was a factor of two greater with a neon buffer.