Analysis of scattering from fiber waveguides with irregular core surfaces.

The scattering from clad fiber optical waveguides that have cores whose surfaces are perturbed in various ways is calculated with the induced dipole method. Such scattering is of interest because it can couple the guided modes of a multimode waveguide, thereby reducing the temporal dispersion. The five surface deviations considered are a rectangular radial step, a sinusoidal perturbation of the radius, a sinusoidal meander of the core, a deviation where the core alternates periodically along the core axis between a y-extended elipse and a z-extended elipse (x is the core axis), and a helical meander of the core axis.