Quantum interferences govern phase delays in w-2w strong field ionization

ARBÓ, D G; LÓPEZ, S D

Salta

Conferencia; Conferencia Latinoamericana de Colisiones Inelásticas en la Materia; 2022

Universidad Nacional de Salta y IAFE

In this work, we develop a strong-field non-perturbation theory of the electronic photoemis-sion process in atomic hydrogen due to a two-color for visible frequency and its first harmonic w-2w [Ti:Sapphire laser (800 nm) to-gether with the first harmonic (400 nm)] linearly polarized short laser pulse in the multip-hoton regime. We introduce a general theory based on the saddle point approximation (SPA) to study phase delays of photoelectrons. We focus on the extraction of the phase shifts using directional emission in the forward direction. We calculate the ionization time of each interfering electron trajectory, analyzing the dependence of the electron emission as a function of the relative phase between the w-2w fields within the strong field approximation.