Photoionization of h atom in synthesized two-color laser fields

We theoretically investigate the photoionization of H atom in two-color laser fields synthesized by one circularly polarized laser pulse and one linearly polarized laser pulse. In this kind of two-color laser fields, the circularly polarized laser pulse is firstly turned on, and after a time delay & tau; the linearly polarized laser pulse will be turned on. Our results show the difference of the ionization rate becomes smaller and smaller with increasing the time delay & tau;. Due to the appearance of linearly polarized laser field, the rescattering ionization process happens and is dependent on its intensity and the time delay & tau;. If the intensity of the linearly polarized laser is lower than that of the circularly polarized laser, the rescattering ionization process is weak, and it becomes more weaker with increasing time delay. The characteristic plateau in the photoelectron energy spectra and the prominent spiderlike structures are reproduced by enhancing the linearly polarized laser intensity. Our results show that this kind of two-color laser field can be used to control the laser-induced rescattering ionization processes.