Nonlinear wave propagation in an asymmetric converging Y junction.

Nonlinear wave propagation in an asymmetric converging Y junction, which consists of a nonlinear cladding, a linear film, and a linear substrate, is studied. The nonlinear dispersion curves of the successive sections of the Y junction are calculated to be used to illustrate the evolutions of the eigenmodes. The field incident from the nonlinear thinner branch can evolve into the symmetric mode of the stem with a high coupling efficiency. An insertion coupler for a time-multiplexed loop is suggested.