Third harmonic generation in rare gas solids

Coherent radiation is generated around 94, 112, and 118 nm by frequency tripping in Ar and Kr crystals. The center wavelength of the tuning ranges can be shifted by 0.1 to 0.2 nm with temperature. The spectral widths of the tuning ranges in Ar increase from 0.03 to 0.15 nm for a reduction of the sample thickness from 3 mm to 5.5 mu m. The conversion efficiency saturates for film thicknesses around 50 mu m due to reabsorption. Surface damage limits the conversion efficiency to 3.10/sup -7/ for 15 ns long pulses, and a value of 6.5.10/sup -6/ has been already obtained for ps pulses. Analytical and numerical solutions for the wave equations, including reabsorption, are derived and a consistent description of the properties of third harmonic generation in rare gas crystals is provided.<
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