Scattering of Light by a Single Imperfection Core in a Waveguide System

Abstract

An asymptotic expansion of the amplitude of the scattered wave by an imperfection core in a waveguide system is derived and it is shown that the scattered wave is partially canceled by the direct wave at large distance and a shadow takes place. For z → ∞ where z is the distance along the waveguide axis the amplitudes of the direct and scattered waves decrease in proportion to z^-1/2 and in the shadow region the amplitude of the sum of both waves decreases in proportion to z^-3/2. To supplement the analytical results some numerical examples are shown.