Wavelength scaling of efficient high-order harmonic generation by two-color infrared laser fields

We theoretically investigate and demonstrate a better wavelength scaling of harmonic yield in a two-color infrared field. By mixing a Ti:sapphire assistant field with the infrared driving field, we show that high harmonic generation is enhanced and the harmonic yield scales as lambda(-3)-lambda(-4) in the plateau region, which falls more slowly as the increase of the driving laser wavelength. compared with lambda(-5)-lambda(-6) in a one-color infrared field.