Frequency doubling of femtosecond laser pulses in three dimensional nonlinear photonic crystals

Quasi-phase matched nonlinear frequency conversion in three dimensional nonlinear photonic crystals (NPCs) has been considered for implementation of the second harmonic generation of transform-limited and chirped femtosecond laser pulses. Spatial distribution of the second harmonic intensity is shown to be caused by Cherenkov- and Raman-Nath-type nonlinear diffraction. These types of nonlinear diffraction may occur simultaneously resulting in an efficient multi-order nonlinear diffraction in the Bragg regime, which can be realized by a proper choice of the modulation period of NPC structure in longitudinal direction for considered transverse diffraction order. Three dimensional NPCs open up new possibilities for ultrafast nonlinear photonics and parametric interactions in optics.

Automated summary

Quasi-phase matched nonlinear frequency conversion in three dimensional nonlinear photonic crystals enables efficient multi-order nonlinear diffraction, which can be achieved by a proper choice of the modulation period of the NPC structure. The spatial distribution of the second harmonic intensity is influenced by Cherenkov- and Raman-Nath-type nonlinear diffraction. These findings open up new possibilities for ultrafast nonlinear photonics and parametric interactions in optics.