Phase-controlled switching in nonlinear multiport fiber couplers

Abstract

The background of the phase-controlled switching behavior of nonlinear multiport couplers is investigated. For the two-core device a direct correlation between the concept of nonlinear eigenmodes and the spatial dynamics can be found. In aligned and triangular three-core geometries the interpretation of the dispersion relations of the nonlinear eigenmodes, as well as the introduction of power portraits, turns out to be useful in identification of those initial states that prepare the system for sensitive switching operations. Some opportunities for optimizing the input–output characteristics are discussed.