Directional correlation in direct and sequential double ionization of model atoms

We discuss directional dependence in the time development of spatia wavefun ctions, which includes jet formation, for two-electron model atoms exposed to intense laser fields. Two competing scenarios for double ionization are evident: (1) both electrons emerge simultaneously from the core region and on the same side of the nucleus, and (2) the electrons detach on opposite s ides but not simultaneously. The importance of the electron-electron repuls ion contribution to the competing processes is investigated for various las er intensities. (C) 2000 Optical Society of America.