CC BY 3.0 UnportedBecker, W.Milošević, D.B.2023-06-052023-06-052017https://oa.tib.eu/renate/handle/123456789/12369http://dx.doi.org/10.34657/11401Above-threshold ionization (ATI) of atoms by a strong bicircular laser field is investigated using the strong-field approximation and the quantum-orbit theory. The bicircular field consists of two coplanar counterrotating circularly polarized fields with a frequency ratio of 2:1. The velocity map of the angle-resolved ATI spectra, both for direct and rescattered electrons, reflects the shape of a parametric plot of the bicircular field and its symmetries. It is shown that the main characteristics of the ATI spectra can be explained using only a few quantum orbits having short travel times. We also analyze a recently discovered [Phys. Rev. A 93, 052402(R) (2016)] bicircular-field-induced spin asymmetry of the ATI electrons and show that the momentum dependence of the spin-asymmetry parameter is stronger for longer wavelengths.enghttps://creativecommons.org/licenses/by/3.0530Atom lasersIonizationLaser theoryTravel timeArticleKonferenzschrift