Theory of CW Light Propagation in Three-Core Nonlinear Directional Couplers

The theory of stationary propagation of laser radiation in nonlinear directional couples (NDCs) usually assumes that the propagation constants β depend on the wave intensity J. At present time properties of two-core NDCs whose propagation constants contain the Kerr correction [1–3] have been studied in detail. A system of nonlinear differential equation describing the propagation of light in coupled parallel fibres has been constructed and analytic solutions of these equations in terms of elliptic functions have been obtained.