Double-ionization mechanisms of the argon dimer in intense laser fields

Journal Article · Thu Jul 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.013412· OSTI ID:21442938

Ulrich, B; Vredenborg, A; Malakzadeh, A; Meckel, M; Cole, K; Jahnke, T; Doerner, R ^[1]; Smolarski, M ^[2]; Chang, Z ^[3]

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1. Institut fuer Kernphysik, Goethe Universitaet, Max-von-Laue-Strasse 1, D-60486 Frankfurt (Germany)
2. Department Physik, ETH Zuerich, Wolfgang-Pauli-Strasse 16, CH-8093 Zuerich (Switzerland)
3. Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)

We have measured the two-site double ionization of argon dimers by ultrashort laser pulses leading to fragmentation into two singly charged argon ions. Contrary to the expectations from a pure Coulomb explosion following rapid removal of one electron from each of the atoms, we find three distinct peaks in the kinetic energy release (KER) distribution. By measuring the angular distribution of the fragment ions and the vector momentum of one of the emitted electrons for circular and linear laser polarization, we are able to unravel the ionization mechanisms leading to the three features in the KER. The most abundant one results from tunnel ionization at one site followed by charge-enhanced tunnel ionization of the second atom. The second mechanism, which leads to a higher KER we identify as sequential tunnel ionization of both atoms accompanied by excitation. The third mechanism is present with linearly polarized light only. It is most likely a frustrated triple ionization, where the third electron does not escape but is trapped in a Rydberg state.

• OSTI ID: 21442938
• Journal Information: Physical Review. A, Vol. 82, Issue 1; Other Information: DOI: 10.1103/PhysRevA.82.013412; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
ARGON
ARGON IONS
ATOMS
DIMERS
ELECTRON EMISSION
ELECTRONS
EXCITATION
LASER RADIATION
PHOTOIONIZATION
PHOTON-MOLECULE COLLISIONS
POLARIZATION
PULSES
VISIBLE RADIATION
CHARGED PARTICLES
COLLISIONS
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ELEMENTS
EMISSION
ENERGY-LEVEL TRANSITIONS
FERMIONS
FLUIDS
GASES
IONIZATION
IONS
LEPTONS
MOLECULE COLLISIONS
NONMETALS
PHOTON COLLISIONS
RADIATIONS
RARE GASES