Modal analysis of optical fibers with symmetrically distributed nonuniform cores

This paper describes the modal analysis of optical fibers with symmetrically distributed multiple cores. Each core has an identical, axially symmetrical, and nonuniform refractive index profile. Group theoretical approach is applied to treat the symmetry of the waveguide structure. The point-matching method combined with the staircase-approximation method is used to take into account complex boundary conditions and complex refractive index distributions. The numerical computation based on this approach has been found to be very effective.