Rotating disk valve for use in a differentially pumped gas system

Transmitting materials that can support reasonable pressure differentials and high laser intensities are not available in the extreme ultraviolet (XUV) spectral region below 100 nm. The present rotating disk system is designed to provide a clear aperture for XUV radiation on a pulsed basis while minimizing gas loss due to differential pumping. A comparison of the rotating disk valve and recent applications of pulsed supersonic nozzles to the generation of coherent radiation in the XUV by nonlinear laser mixing in gases is made. In an experimental setup designed to generate coherent XUV light near 92.3 nm in krypton, the rotating disk resulted in a gas savings of about a factor of 9 over an open aperture of the same size.