Spatio-temporal delay in photoionization by polarization structured laser fields

TL;DR

This paper investigates how textured, polarized laser fields influence photoelectron spectra and demonstrates potential for sub-wavelength atomic position detection using attosecond streaking techniques.

Contribution

It introduces a method to determine atomic positions within laser spots by analyzing angular-dependent photoelectron spectra in structured laser fields.

Findings

Photoelectron spectra depend on atom position within the laser spot.

Angular dependence of photoionization amplitude and phase varies with atom location.

Potential for sub-wavelength atomic position detection using attosecond streaking.

Abstract

Focused laser fields with textured polarization on a sub-wavelength 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 reported here 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 sub-wavelength scale. The proposal and its illustrations underline the potential for the detection of the atomic position based on attosecond streaking methods.