Curvature-induced oscillations of the loss of leaky modes in optical fibers: a ray analysis

Abstract

A new curvature loss formula for leaky modes is derived from a direct application of the volume current method. This formula is confirmed in the particular case of a leaky LP01 mode in a DIC fiber with a moderate curvature, by means of combination of the standard analytical perturbation analysis of DIC fibers with a ray analysis of the field in the outer cladding. Curvature induced oscillations of the leakage loss are predicted, due to an interference effect. The validity of the new loss formula for larger curvatures is discussed.