Improved ultraviolet second-harmonic generation at elevated repetition rates from a medium-scale copper-vapor laser

We report significant improvements in ultraviolet (UV) power generation at elevated pulse-repetition frequencies (10/spl ges/kHz) from a frequency-doubled copper-vapor laser (CVL), employing a Ne-H/sub 2/ buffer gas. In particular, UV powers of 1.3 W and 0.6 W at 255 nm (SHG green) were generated at 10 kHz and 20 kHz, respectively, when using H/sub 2/ additive in a medium scale (nominally 20 W) CVL oscillator. These results represent improvements of 6.5/spl times/ and /spl sim/100/spl times/, respectively, over the UV powers obtained for pure neon-buffer gas. The enhanced UV powers are directly related to the improvement in high-beam quality extraction from the CVL due to the beneficial effects of the H/sub 2/ add-gas on CVL gain characteristics.<
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