Time-dependent studies of photon-induced processes in He

The fully three-dimensional Schr\"odinger equation for two-electron systems, such as He exposed to intense laser pulses, has been numerically solved within the time-dependent close-coupling scheme. The Real-Space Product Formula (RSPF) has been implemented in our calculations in the time propagation and is found to have advantages over other propagators. The resulting cross-sections of two-photon double ionization and the decay rates for autoionization states are in very good agreement with those obtained in experiments and by other methods. In addition, the time-dependent method enables us to examine the detailed dynamics of these processes.