Generation of 1182-Å radiation in phase-matched mixtures of inert gases

Coherent radiation at 1182 Å is obtained by third-harmonic generation in a phase-matched mixture of Xe and Ar. For generation from 3547 to 1182 Å, Xe is negatively dispersive, and phase matching is obtained at a ratio of Xe:Ar=1:430. A conversion efficiency of 2.8% is obtained at an input power of 13 MW. As predicted by theory the conversion efficiency increases linearly to the limit of our available input power.