Theoretical investigation of core geometry variation influence on a few-mode optical signal distortion during propagation over silica graded-index multimode fiber with low DMD

Abstract

In recent works an alternative method for design of silica GeO2-doped graded-index multimode optical fibers 50/125 with low differential mode delay (DMD) was introduced. It is based on synthesis of special refractive index profile, providing the equalization of guided mode group velocities. A theoretical approbation of introduced fibers under the modeling of fiber optic link showed good results for a few-mode regime of high-speed laser-based serial data transmission. However on practice a different distributed core geometry parameter variation occurs in real optical fibers due to techniques features of preform manufacturing and fiber drawing. Here results of fiber optic link modeling with proposed multimode fibers 50/125 with low DMD under core diameter variation and refractive index profile deviation from the optimal form, and estimation of their influence on a few-mode optical signal distortion are represented.