Giant bistable shifts for one-dimensional nonlinear photonic crystals

It is found that there exists a hysteretic response between the incident intensity and the lateral shift for a one-dimensional photonic crystal containing a nonlinear defect. The lateral shift can be greatly enhanced when the incident intensity decreases from a value higher than the switch-up threshold of optical bistability and reaches the maximum at the switch-down threshold. It is also found that the hysteresis is strongly dependent on the nonlinear defect, the incident angle, and the incident frequency. The validity of the theoretical analysis is demonstrated by numerical simulations for a Gaussian beam.