High-power Lyman-alpha source generated with an ArF excimer laser.

We report high-power vacuum-ultraviolet (vuv) generation at the Lyman- alpha wavelength of 121.6nm , using a simple experimental system. vuv radiation is produced through two-photon-resonant difference-frequency mixing with a tunable ArF excimer laser and a Nd:YAG-pumped dye laser. Using phase-matched mixtures of Kr and Ar at a total pressure of 650 mbar, we produced 7-microJ energies at Lyman- alpha in approximately 5ns (1.3kW) , as measured directly with a pyroelectric energy probe. Measurements indicate that higher powers are possible with system optimization. A tuning range of 0.1nm was achieved for a fixed gas mole fraction at a total pressure of 650 mbar. Qualitative agreement is found between measured tuning profiles and theoretical predictions.