Abstract

Fiber-optic components and systems using highly elliptical core two-mode fibers are becoming attractive because of the stable transverse mode pattern as well as unique phase and group velocity propagation characteristics.^[1,2] Understanding the propagation behavior of both the fundamental and second-order modes under various perturbations is important for extending the application areas of such fibers. A two-mode fiber with a highly elliptical core guides two linearly polarized modes, along the major (x) and minor (y) axes of the core ellipse, for each of the first (lp₀₁) and the second (LР₁₁) order spatial modes. Although the effects of perturbations on the mode propagation in single-mode fibers have been extensively studied, little work has been done for higher order modes in few mode fibers. In this paper, we present the perturbation effects on the differential phase shift between two spatial modes in each polarization and between two polarization modes in each spatial mode, for two mode fibers.

© 1988 Optical Society of America