Abstract

Intrinsically localised states in waveguide arrays [1] represent discrete analogues of solitary waves in continuous media and are thus considered as a promising basis for all-optical switching, steering and routing. All-optical switching in nonlinear waveguide arrays has already been experimentally observed [1]. In such cubically nonlinear arrays nonlinear coupling between two components with different frequencies or polarisations results in cross-phase modulation and energy exchange between them. The dynamics of the system is described by a set of coupled discrete nonlinear Schrödinger equations [2]. The existence of bright strongly localised vectorial modes (SLMs or bright simultons) have been demonstrated recently [2] whereas in the present work we derive approximate analytical solutions for dark kink-like as well as for dark-bright simultons and study their background stability.

© 1998 IEEE