Spatiotemporal delay in photoionization by polarization-structured laser fields

Abstract

Focused laser fields with textured polarization on a subwavelength scale allow extracting information on electronic processes which are not directly accessible by homogeneous fields. Here we consider photoionization in radially and azimuthally polarized laser fields and show that, due to the local polarizations of the transversal and the longitudinal laser electric field components, the detected photoelectron spectra depend on the atom position from which the electron originates. The calculation results show the angular dependence of the photoionization amplitude, the quantum phase, and the time delay of the valence shell electrons as the parent atom's position varies across the laser spot. We discuss the possibility of using the photoelectron spectra to identify the position of the ionized atom within the laser spot on the subwavelength scale. The proposal and its illustrations underline the potential for the detection of the atomic position based on attosecond streaking methods.