Enhanced SHG in planar nonlinear waveguide reproducing a 1-D PBG

Summary form only given. Second harmonic generation (SHG) is investigated in planar waveguide geometry under conditions for which the use of a linear grating fabricated on top of the waveguide reproduces a photonic band-gap structure. The fundamental mode of the guide, which coincides with the fundamental pump frequency, is tuned at the photonic band edge resonance in order to enhance field localization effects. However, the linear grating alone is not able to produce both field confinement and phase-matching of the SHG process. Phase-matching is obtained with the additional modulation of the nonlinear susceptibility χ⁽²⁾, as in conventional quasiphase-matching schemes. The conversion efficiency achieved using both linear and nonlinear gratings is orders of magnitude greater than that of a quasi-phase-matched device of the same length. Enhancement of the second harmonic generation (SHG) in Cerenkov configuration is also investigated.