The Attoclock in Laser-Assisted Atomic Photoionization

We present a theoretical investigation of the attoclock method in laser-assisted photoemission (LAPE) processes. We analyze atomic photoionization driven by a short XUV pulse assisted by a circularly polarized strong infrared (IR) laser under accessible experimentally conditions. We calculate three-dimensional photoelectron momentum distributions (PMDs) in order to extract time delays from their angular information based on the attoclock principle. Furthermore, we explore different XUV parameters to determine the optimal achievable temporal precision for the laser-assisted attoclock (LAAC). The analyses performed within the the strong-field approximation (SFA) are further supported by improved Coulomb methods, including the Coulomb–Volkov approximation (CVA) and numerical solutions of the time-dependent Schrödinger equation (TDSE). Our work lays a theoretical foundation for understanding time-resolved electronic dynamics in cutting-edge ultrafast experiments of photonic collisions.