Interaction of high-power laser pulses with atomic media. I. Spontaneous fields in multiphoton ionization

Abstract

A theoretical study of static electromagnetic field generation due to laser radiation force in multiphoton ionization of atomic media is presented. The static fields are spontaneously induced in atomic media and have electric field components in the radial and axial directions of the incident laser beam and an azimuthal magnetic field component. Multiphoton ionization process, which is inevitably apt to occur in the interaction, significantly enhances the spontaneous fields. Numerical calculations of the fields generated in atomic sodium vapor and helium gas have been made, assuming an incident picosecond Nd-doped yttrium aluminum garnet laser pulse. The results show the characteristic natures and magnitude of the spontaneous fields.