Phase modulation in the process of third harmonic generation

Using the spectral approach for description of the processes in nonlinear optics, by numerical calculations we obtain the dependences of the third harmonic generation (THG) on the output spectra and spectral energy, spectral width and spectral barycenter in the presence of quadratic and cubic spectral phase terms in the input. The main equation that describes the evolution of the spectral properties for the process of THG is derived. The suggested model could be applied also for analysis of a few order high harmonics.