NUMERICAL STUDY OF SOLITON SWITCHING IN ACTIVE 3-CORE NONLINEAR FIBERCOUPLERS

A numerical investigation, based on the use of a finite-element-based beam propagation algorithm, of all-optical switching of solitons in th ree-core nonlinear fiber couplers in the presence of gain is presented . The numerical algorithm is described in detail. Linear gain is found to lead to sharper transmittance characteristics, a considerable lowe ring of the switching powers, and also to an increase in the power exc hange between the input and center core for a nearest-neighbor core ar rangement. As in the case of a two-core nonlinear fiber coupler, the f inite gain bandwidth is found to lead to the deterioration of the swit ching characteristics.