Study Reveals Enhanced Nondipole Momentum Effects in Triple Ionization of Atoms Using Mid-Infrared Lasers
Researchers using a three-dimensional semiclassical model have found that triple ionization of neon atoms driven by intense mid-infrared laser pulses produces a large positive momentum offset along the laser propagation direction, an effect absent in the dipole approximation. This offset grows significantly with increasing laser wavelength, driven in part by the magnetic field component of the laser acting on bound electrons, which compensates for weaker recollisions at longer wavelengths. The findings suggest 1200 nm as an optimal wavelength for experimentally observing momentum signatures tied to correlated three-electron escape.
A new preprint on arXiv investigates how nondipole effects manifest in the triple ionization of neon atoms when driven by intense infrared and mid-infrared laser pulses. Using a three-dimensional semiclassical model that fully incorporates nondipole physics and the Coulomb singularity in electron-core interactions, the authors identify a substantial positive average momentum offset along the laser propagation axis — an effect that disappears entirely under the dipole approximation. This momentum offset increases markedly as the laser wavelength grows, a trend observed across all triple ionization events and across both direct and delayed ionization pathways. The authors attribute this wavelength dependence to the growing influence of the laser's magnetic field on bound electrons, which counteracts the diminishing recollision strength at longer wavelengths. The study covers 11 figures across 10 pages and identifies 1200 nm as a particularly favorable wavelength for future experimental measurements of correlated three-electron escape dynamics.
What's missing
As a preprint, this work has not yet undergone peer review. The study relies entirely on semiclassical modeling; experimental validation of the predicted momentum offsets and the proposed 1200 nm optimal wavelength has not yet been performed.
What different sources said
- arXiv physicsCenter
Enhanced nondipole momentum offsets in triple ionization of atoms driven by mid-infrared laser fields
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