Enhanced harmonic generation by bichromatic laser fields

With the help of a weak linearly polarized low-frequency held, we study hig h-order harmonic generation in a circularly polarized high-frequency held. Although the low-frequency field is not intense enough to ionize the atom, it can accelerate the electron more efficiently. As a result, the applicati on of this field can generate harmonics with a much higher energy compared to the monochromatic case.