On The Use Of Multiple Photon Processes In Krypton For Laser Guiding Of Electron Beams

Abstract

Neutral krypton atoms were excited from the ground state 4p6 1S0 to the 4p5 6p[3/2]2 state by a resonant two-photon absorption from a line- narrowed ArF excimer laser operating at 193.41 nm. A third photon, absorbed while the atom is in the excited state, ionizes it. Excited state and ion densities were theoretically computed using a stvdard,rate-equation analysis. The irradiance levels used (1-5x10 8 W/cm2) were too low for significant ground and excited state ac Stark and Rabi effects. The photon detection system was calibrated with a standard tungsten lamp. Ion signals wel3 measured with known electrical components. The resonance results were compared with predictions of non-resonant ionization based on a standard formulation. The ion and excited state densities have been used with a modified electron beam propagation code (IPROP) to model such propagation in a low pressure laser-excited krypton channel. The modifications included the effects to field ionization of the excited krypton atoms. Implications for guiding of e-beams using ArF excited krypton are discussed.© (1989) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.