Research and application of preserving-structure algorithm of high-order harmonic generation spectrum of one-dimensional He+ by a two-color laser field

The high-order harmonic generation spectrums of He+ irradiated by the two-color coherent laser field are researched by numerically solving the 1-D time-dependent Schr dinger equation using symplectic algorithm. The computational results show that great changes have already taken place at the emission of the high-order harmonics and the efficiency of the harmonic generation increases greatly and it averagely increases 103 times in the plateau, despite the fact that the intensity of the higher frequency laser is only 10% of the initial field in the two-color coherent field. The efficiency of the high-order harmonics is enhanced by nearly four orders of magnitude relative to the monomer field; moreover, the corresponding order of the higher frequency field is enhanced by about five ord