Evolution of the transverse photoelectron momentum distribution for atomic ionization driven by a laser pulse with varying ellipticity

TL;DR

This paper investigates how the transverse photoelectron momentum distribution changes with laser pulse ellipticity during atomic ionization, revealing a transition from cusp-like to Gaussian-like distributions and validating the strong-field approximation at high ellipticity.

Contribution

It demonstrates the evolution of the transverse momentum distribution with ellipticity and confirms the accuracy of the strong-field approximation for near-circular polarization.

Findings

Distribution transitions from cusp-like to Gaussian with increasing ellipticity

Strong-field approximation is quantitatively accurate at high ellipticity

Transverse momentum distribution depends strongly on laser polarization

Abstract

We consider the process of atomic ionization driven by a laser pulse with varying ellipticity. We study distribution of the momenta of the photoelectrons, ionized by a strong laser field, emitted in the direction perpendicular to the polarization plane (transverse distribution). We show, that with changing laser pulse ellipticity, the transverse distribution evolves from the singular cusp-like distribution for the close to linear polarization to the smooth gaussian-like structure for the close to circular polarization. In the latter case, when the ellipticity parameter $\epsilon\to 1$ the strong-field approximation formula for the transverse momentum distribution becomes quantitatively correct.