The transfer matrix method is widely used to calculate the electromagnetic waves dispersion. In thispaper, we have investigated the second harmonic generation in a one-dimensional structure includingLiTaO3 ferroelectric. Using the transfer matrix method, we obtain the second harmonic efficiency. Inthis article, in the structure of nonlinear photonic crystals, the linear and nonlinear optical parametersare changed periodically, which causes the second harmonic conversion efficiency to be several timesgreater than the conversion efficiency of a nonlinear structure based on conventional quasi-phasematching (QPM). The reason for this is that in the system discussed in this paper, the presence ofeffects of band gap edges causes the density of states of the electromagnetic fields is increased, thegroup speed of the electromagnetic waves is decreased (as a result, the interaction time is increased)and local field is boosted. As a result of these three factors, the nonlinear optical interaction iseffectively strengthened.
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