Investigation of coupled third harmonic generation in one-dimensional defective nonlinear photonic crystals

One-dimensional defective photonic crystals containing nonlinear material for coupled third harmonic generation (CTHG) have been designed. The general solution of the CTHG in such structure has been derived. The wavelengths of the fundamental wave (FW), second harmonic generation (SHG), and CTHG have been designed to lie at the defect states in different photonic band gaps by employing the simulated annealing (SA) method. Due to the strong location, low group velocity, and spatial phase locking, the conversion efficiencies of the SHG and CTHG have been greatly enhanced. Designed structure for multiple frequencies CTHG is also demonstrated.