A powerful and accurate pseudostate method has been used to study two-photon ionization using elliptically polarized light. Calculations are made for ionization from the ground state as well as from the metastable $2s$ state of atomic hydrogen. The range of the wavelength chosen is such that it corresponds to two-photon ionization, i.e., 900–1700 Å for ionization from the ground state and 4500–7250 Å for ionization from the $2s$ state. It is found that at a given wavelength the ellipticity of the incident radiation modifies the ionization cross section substantially.

• Received 2 March 2001

DOI:https://doi.org/10.1103/PhysRevA.64.043404