Abstract
At very high light intensities, the electron energy spectrum in multiphoton ionization (MPI) spectroscopy of even the simplest atoms changes from a single, well defined threshold peak into multiple peaks, separated from one another by the photon energy. This phenomenon is generally referred to as 'above-threshold ionization' (ATI). The original experiments investigating ATI used relatively long laser pulses, with the result that amplitudes, energy widths and angular distributions of the individual photoelectron peaks depended on the laser intensity. In addition, the widths of the peaks, as well as their absolute energy positions, changed according to the temporal width of the laser pulse. These dependencies were not intrinsic to the ionization process, but rather were all eventually ascribed to ponderomotive forces exerted on free photoelectrons by the laser focus. The ponderomotive effects frustrated comparisons between theoretical calculations and experimental data.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Physics B: Atomic, Molecular and Optical Physics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
