Production of sum-frequency radiation and ‘‘even’’ harmonics from the mixed 1ω (1053 nm) and 2ω (527 nm) field is observed and compared to measurements of the relative conversion efficiency of the independent fields. By controlling the relative polarization of the two fields, we can control the mixing efficiency and produce coherent extreme ultraviolet (XUV) radiation polarized orthogonally to the strong driving field. Extension to produce XUV radiation of arbitrary polarization is discussed.

• Received 7 September 1993

DOI:https://doi.org/10.1103/PhysRevA.48.R4051