Strong Laser Fields
Welcome to the Strong Laser Fields Group at the Department of Molecular and Optical Physics, University of Freiburg, Germany.
Electron Imaging Study of Multiphoton Ionization of Neon
H. Helm1 and M. J. Dyer2
1Department of Molecular and Optical Physics, Albert-Ludwigs-Universität, Hermann-Herder-Strasse 3, D-79104 Freiburg, Germany
2Molecular Physics Laboratory, SRI International, Menlo Park, California 94025
We have investigated short-pulse multiphoton ionization of neon at wavelengths between 305 and 330 nm,
at intensities between 5.1013 and 5.1014 W/cm2.
Photoelectron energy- and angular-distributions are recorded in an electron imaging spectrometer.
We find resonant transitions to the ac-Stark shifted 5-photon states 2p53d and 2p54s to be dominant ionization paths at the shorter wavelengths.
At wavelengths >310 nm these states lie above the 5-photon energy and are therefore closed channels.
Under these conditions nonresonant 6-photon ionization occurs at the lowest intensities.
At higher intensities, the ponderomotive shift closes the 6-photon ionization threshold, and a new resonant path opens via 6-photon resonances with eve
n parity. This path gives rise to angular distributions that are characteristic for intermediate states with 2p5nf-character.
© World Scientific, Singapore, p. 468-73 (1995)
"Atomic and Molecular Physics"
in: Proceedings of the Fourth US/Mexico Symposium on Atomic and Molecular Physics:
Antigua Hacienda De Galindoi, San Juan del Râio, Querâetero [i.e. Querâetaro)
Editors: I. Alvarez, C. Cisneros and T. J. Morgan