Bistable Goos-Hänchen shift owing to leaky-mode excitation in a slab waveguide with Kerr nonlinear medium

Abstract We investigate the nonlinear Goos-Hänchen shift of light beam reflected from a prism-coupled leaky waveguide containing Kerr medium. As the incident power changes, the system can be switched between two states, total internal reflection and frustrated total reflection, owing to the inherent positive feedback from the intensity-dependent guiding mode resonance. Then the reflectance exhibits optical bistability, meanwhile the lateral shift of reflected light beam shows hysteresis behavior as well. It is found that the transition between the two stable states is related to the excitation of leaky mode in waveguide, which results from the modulation of electric field in the nonlinear substrate. We also analyze the effects of system parameters on the bistable Goos-Hänchen shift. The thresholds as well as the width of the hysteresis curve is sensitive to the thicknesses of the gap layer and the guiding layer which determine the resonance angle. The bistable lateral displacement in the slab waveguide may have potential applications in optical switching, beam steering, etc.