Double ionization of helium in an elliptically polarized laser field

In this letter we discuss the double ionization of helium in intense, elliptically polarized laser fields. We extend a model previously used for linear polarizations to the case of a two-dimensional model atom subject to a laser field of arbitrary ellipticity. Our results show a decrease in the efficiency of the non-sequential double ionization as the ellipticity of the driving field is increased, consistent with the recollision picture of double ionization. Our results are in qualitative agreement with previous experimental measurements. (author). Letter-to-the-editor