SWITCHING DYNAMICS OF THE REFLECTED FIELD IN A NONLINEAR GRATING COUPLER

Using a modal theory, we study the dynamics of a two-dimensional finit e beam reflected by a nonlinear grating coupler. Different algorithms are proposed to calculate the linear as well as the nonlinear coupling coefficients. We show that this nonlinear grating coupler can be opti mized with respect to switching contrast and power. We compare our res ults with the experimentally determined switching behavior of a silico n-on-sapphire coupler and study its application as a fast saturable ab sorber.