Near-atmospheric-pressure xenon excimer laser

Oscillation at 172 nm for 200 nsec has been observed at a pressure of 1.5 atm of xenon with a 1-m length of gain medium pumped by a 200-kV 7-A/cm2 1-μsec electron beam. The observed behavior agrees with calculations based on the excited-state mixing model for this new operating regime. The results support model predictions that a modest increase in excitation rate (about a factor of 2) would yield quasi-steady-state laser oscillation with an intrinsic efficiency near 5%, a fluence of ∼1 J/cm2, and a peak intracavity two-way flux of ∼50 MW/cm2. In optimized laser amplifier designs, significantly higher amplifier efficiencies should be possible.