Multiphoton Ionization Induced by Circularly Polarized Radiation

Abstract

The ratio ${\ensuremath{\mu}}_{N}$ of the cross section for circularly polarized light to that for linearly polarized is numerically investigated for $N$-photon ionization of atomic hydrogen. For $N<4$, it appears that the gain factor is greater than unity. For $N\ensuremath{\ge}4$, the ratio ${\ensuremath{\mu}}_{N}$ is generally smaller than unity and decreases when the multiphoton order $N$ increases.