Retrieving intracycle interference in angle-resolved laser-assisted photoemission from argon

HUMMERT, JOHAN; KUBIN, MARKUS; LOPEZ, SEBASTIAN D.; FUKS, JOHANNA I.; MORALES, FELIPE; VRAKKING, MARC J. J.; KORNILOV, OLEG

JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2020 vol. 53

0953-4075

We report on a combined experimental and theoretical study of XUV ionization of atomic argonin the presence of a near-infrared (NIR) laser field. Using a table-top source of wavelength-selectedfemtosecond XUV pulses in combination with a velocity map imaging spectrometer we record angleandenergy-resolved photoelectron distributions and simulate the experimental data by solving thetime-dependent Schr¨odinger equation ab initio. In order to compare with the experimental data weaverage the calculated energy-angle probability distributions over the experimental focal volume fordifferent values of the magnetic quantum number of the photoelectron. This averaging procedurewashes out the intracycle interference pattern, which would otherwise be observed in the form ofangular modulations of the photoelectron spectra. We recover these modulations experimentallyand in the simulations by evaluating the difference between two averaged distributions that areobtained for slightly different NIR laser field intensities.