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Topical Meeting on Laser Techniques in the Extreme Ultraviolet

Non-Linear Mixing

K. H. Welge

Published Jan 1, 1982• 0 citations

Abstract

We report investigations with tunable VUV radiation, employing VUV generation in regions down to the cut-off wavelength of lithium fluorid crystal (~ 110 nm) by frequency tripling of tunable UV from dye laser. -Experiments on multiphoton excitation and ionization of atomic hydrogen with tunable VUV light at Lyman-α, have been carried out with the following objectives: (1) sensitive H and D atom detection by two-photon ionization i. e. 1s ω Lyα → 2 p ω uv → ion , (2) two-photon ionization of H with high resolution at Lyman-α to resolve the hyperfine groundstate doublet, aiming at the production of polarized protons, (3) state selective production of high Rydberg states ( 1 s ω Lyα → 2p ω uv → ns, nd ) , and their ionization, (4) Doppler line shape spectroscopy at Lyman-α applied to recoil energy and momentum distribution measurements of H and D atoms in dissociation processes. -Depending on the objective, different experimental conditions and systems have been employed, for instance atomic beam configuration, mass-spectroscopic ion detection, field ionization in cryogenetic environment, and for Doppler measurements laser induced fluorescence.

DOI: 10.1364/euvs.1982.wa1

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