The interaction and switching of optical solitons in a nonlinear directiona
l coupler are investigated analytically and numerically. The influence of t
he coupling-coefficient dispersion, the third order dispersion and the Rama
n effect in fibers on these processes are reported. Coupled soliton states
are found, and their stability is checked numerically. Switching characteri
stics of solitons in directional couplers are studied. (C) 1999 Elsevier Sc
ience B.V. All rights reserved.