The probe of electron correlation along the He isoelectronic sequence by intense and short laser pulses

Highlights: • Ab initio study of the sequential two-photon double ionization of He and He-like ions. • Probing electron-electron interaction with intense and short laser pulses. • Demonstration of the important effect of the nuclear charge on the electron dynamic. - Abstract: The two-photon double ionization process along the He isoelectronic sequence (He − Ne⁸⁺) is investigated by solving the full-dimensional time-dependent Schrödinger equation in an intense laser field. The ionization is triggered from the ground state of each system with photons of energy higher than its second ionization potential, in which case the sequential two-electron ejection is allowed. The results of the total two-photon double ionization probability and the energy distribution of ejected electrons demonstrate the important effect of the nuclear charge Z on the dynamics of the interaction between the two ejected electrons.