Strong-field photoionization revisited
Abstract
Over the past thirty years, extensive studies of strong-field photoionization of atoms have revealed both quantum and classical aspects including above-threshold ionization, electron wave-packet drift, quiver and rescattering motions. Increasingly sophisticated spectroscopic techniques and sculpted laser pulses coupled with theoretical advances have led to a seemingly complete picture of this fundamental laser-atom interaction. Here, we describe an effect that seems to have escaped observation: the photoelectron energy distribution manifests an unexpected characteristic spike-like structure at low energy, which becomes prominent using mid-infrared laser wavelengths (λ>1.0μm). The low-energy structure is observed in all atoms and molecules investigated and thus seems to be universal. The structure is qualitatively reproduced by numerical solutions of the time-dependent Schrödinger equation but its physical origin is not yet identified.
- Publication:
-
Nature Physics
- Pub Date:
- May 2009
- DOI:
- 10.1038/nphys1228
- Bibcode:
- 2009NatPh...5..335B