Abstract

Nonresonant sum- and difference-frequency mixing of the fundamental (ω_L) and the second harmonic (ω_uv) output of a powerful narrowband pulsed dye laser excited by a Nd-YAG laser has been investigated in Xe and Kr. The sum-frequency ω_vuv = 2ω_uv + ω_L is tunable in spectral regions of negative dispersion between 110 nm, and 130 nm. The maximum VUV pulse power exeeds 20 W (5 10¹⁰ photons/pulse). The difference frequency ω_vuv ⁼ 2ω_uv − ω_L provides VUV light pulses with up to 60 W (2.3 10¹¹ photons/pulse) at wavelengths between 185 nm and 207 nm. Coherent VUV light of shorter wavelength (159.5 nm to 186.6 nm) is obtained by mixing the UV dye laser radiation with the infrared output (ω_IR) of the Nd-YAG laser (ω_vuv= 2ω_uv − ω_IR). With UV light of shorter wavelength $\left({\text{ω}}_{\text{uv}}^{\prime }={\text{ω}}_{\text{uv}}+{\text{ω}}_{\text{IR}}\right)$ the difference frequency conversions ${\text{ω}}_{\text{vuv}}=2{\text{ω}}_{\text{uv}}^{\prime }-{\text{ω}}_{\text{L}}$ and ${\text{ω}}_{\text{vuv}}=2{\text{ω}}_{\text{uv}}^{\prime }-{\text{ω}}_{\text{IR}}$ allow the generation of VUV light with wavelengths between 122.6 nm and 160 nm. Thus with a single dye laser which is operated in the most efficient operating range of Nd-YAG laser pumped dye lasers (ω_L = 550 − 670 nm) the investigated conversion schemes generate intense coherent VUV light which is continuously tunable between 110 nm and 210 nm.

© 1982 Optical Society of America