Bistable Optical Device Using Guided Mode Excitation in Silicon on Sapphire

Abstract

Intrinsic optical bistable devices generally consist of a nonlinear material in a resonant cavity. The characteristic switching times are limited both by the properties of the nonlinear material and by the cavity filling time. The latter can be reduced if a very short resonant system is considered, and advantage is taken from using an optical waveguide. Nonlinear guided waves received an increasing interest during the last years, but only few experiments have been reported to date. Theoretical calculations have shown that a structure consisting of a nonlinear silicon layer, sandwiched between a sapphire substrate and a silver layer, light being coupled in it by a diffraction grating, can exhibit optical bistability (1). Such a device has been realized and experimental results are reported here.