Limitation of 3547 to 1182 Å conversion efficiency in Xe

We report experiments which indicate that the 3547 → 1182Å conversion efficiency in Xe-Ar mixtures is limited by Kerr-induced dispersion to about 0.9 percent. The mixed frequency third-order nonlinearityχ⁽³⁾(-3ω, 3ω, -ω, ω) significantly alters the index of refraction at 1182 Å in the presence of large power densities at 3547 Å, affecting phase matching. We suggest using a Xe-Mg-Ar mixture to reduce the effect, thus permitting increased efficiencies.