Phase-dependent Coulomb focusing effect in orthogonally polarized two-color laser fields
Phys. Rev. A 112, 013112 – Published 11 July, 2025
DOI: https://doi.org/10.1103/hfr3-dsqx
Abstract
We theoretically investigate the Coulomb focusing effect in an orthogonally polarized two-color (OTC) laser field by numerically solving the time-dependent Schrödinger equation. Based on the photoelectron momentum distribution along the light-propagation direction, the strength of the Coulomb focusing effect across all relative phases in the OTC field is quantified using a unified standard, revealing a phase dependence. Employing a semiclassical model, we conduct a comprehensive study of the underlying mechanism and find that both the unique electron looplike dynamic behavior and the electron birth time distribution play crucial roles. Their respective influences are manifested in two different aspects, i.e., altering the effective interaction time with the ionic potential and changing the proportion of rescattering electrons. We further investigate the phase-modulated Coulomb focusing effect for different atoms in the OTC field. Distinct modulation trends are observed, which arise from the differences in the proportion of rescattering electrons.
