Above-threshold ionization

The angle-integrated photoelectron spectrum resulting from a laser interacting with a hydrogen atom. The x axis marks the electron kinetic energies in eV, whilst the y axis is the differential probability. The first three above-threshold ionization peaks are visible in the image.

In atomic, molecular, and optical physics, above-threshold ionization (ATI) is a multi-photon effect where an atom is ionized with more than the energetically required number of photons.[1] It was first observed in 1979 by Pierre Agostini and colleagues in xenon gas.[2]

  1. ^ Parker, Jonathan; Clark, Charles W. (February 1, 1996). "Study of a plane-wave final-state theory of above-threshold ionization and harmonic generation". Journal of the Optical Society of America B. 13 (2): 371. Bibcode:1996JOSAB..13..371P. doi:10.1364/JOSAB.13.000371.
  2. ^ Bashkansky, M.; Bucksbaum, P.; Schumacher, D. (June 13, 1988). "Asymmetries in Above-Threshold Ionization". Physical Review Letters. 60 (24): 2458–2461. Bibcode:1988PhRvL..60.2458B. doi:10.1103/PhysRevLett.60.2458. PMID 10038359.