In this paper, we propose a new method to study wave propagation in Longitudinally
invariant waveguides with arbitrary index profile. In our method, we keep, in the wave
equation, the second order derivative of transverse wave field with respect to the propagation
direction, which is usually neglected in paraxial approximation utilized in many cases. An
explicit expression for the wave field at any longitudinal position along an optical waveguide
is derived, thus excluding the use of beam propagation algorithm for computation. This study
has demonstrated that our approach yields the same results as those by using a commercial
software in which a beam propagation method with Pade' approximation is used.
Relation:
Hsiuping Institute of Technology Journal 7:167-174
