Energy spectra of photoelectrons formed by atom ionisation in an intense two-color laser field

The energy spectra of photoelectrons, formed at atom above-threshold ionization in the intense two-color laser field are investigated analytically and by numerical calculations by the method of factorization of rescattering amplitude on the basis of pole approximation. The close agreement with results of the classical analysis and numerical calculations of spectra by other authors is received. It confirms applicability of the strong field formalism on the basis of pole approximation used here. (author)