Abstract: A new treatment for the behaviour of both TE and TM non-linear waves in an arbitrary nonlinear material is given. The treatment is based on a recently developed method-the Iterative Eigen. function expansion method (IEEM). Compared with the results of Finite-element method (FEM), this scheme has proven very successful.It is also easily generalized to other nonlinear behaviour studies for varying geometries.

Key words: Nonlinear optical waveguides, eigenfunction expansion