Abstract

All-optical switching devices have attracted considerable attention recently due to their potential for ultrafast switching. Using very rapid electronic nonlinearities in transparent materials, high speed switching free of thermal limitations at high rates can be achieved. A nonlinear directional coupler, first proposed by Jensen [1] and recently demonstrated by Friberg et al [2], is a promising all-optical switch. In this device switching speeds are limited only by the material response and not by transit times. Ideally, the response of such a switch is determined by the instantaneous intensity of the light; however, due to self phase modulation, group velocity dispersion and the finite bandwidth of the element, there will be a limiting switching speed. In this work we report the first study of femtosecond switching in a nonlinear directional coupler, and discuss the implications of nonlinear switching of ultrashort pulses.

© 1988 Optical Society of America