INTERMODAL DISPERSION IN 2-CORE OPTICAL FIBERS

The switching characteristics of a two-core optical fiber can be descr ibed by the beating of the even and odd modes of the composite two-cor e structure. It is shown that the group-delay difference between these two modes can be as large as 10 ps/m. This intermodal dispersion sets a limit on the shortest duration of the optical pulse that can be swi tched effectively in devices that use long lengths of two-core fibers, such as wavelength-division multiplexers, polarization splitters, and nonlinear directional couplers.