An Optical Parametric Amplifier in Photonic Crystals of Nondispersive Medium with Perfect Bloch Phase Matching

One-dimensional photonic crystal of second-order nonlinearity is studied. Among the three waves of the parametric interaction process of down-conversion with a nondispersive medium, two gap-edge localized modes and one travelling-mode are proposed, and an exact phase matching condition is realized using the periodic condition of the Bloch phase. Numerical simulation is implemented by the slow-envelope finite difference time domain method. In the case of a pulse wave pump of amplitude half-width 5.2 x 10^-13s, an intense optical parametric pulse with half-width about 5 x 10^-14s is observed.