Abstract

It has been verified that second-order nonlinear process can cause the energy transfer between interacting waves which results in the modification of phase fronts of interacting waves[1]. Many all-optical switching devices have been demonstrated recently implementing such principle[2,3]. One of the most characteristic features of cascading is that the magnitude of the nonlinear phase distortion itself is a function of wavevector mismatch condition. Also in waveguide geometry, the propagation constant of each existing mode is different. Therefore if two modes are launched together in a second-order nonlinear material, for a specific wavevector mismatch condition, one can introduce larger nonlinear phase shift in one mode than the other. Reported here is all-optical switching using modal interference in a LiNbO₃ channel waveguide.

© 1998 Optical Society of America