Langevin Equation Approach to Mode Coupling in Heated Step-Index Plastic Optical Fibers

Abstract

The Langevin equation is used to investigate the state of mode coupling in step-index plastic optical fibers under varied temperature. The numerical integration of the Langevin equation is based on the computer-simulated Langevin force. The solution matches the experimental data reported previously. We find that elevated temperatures of plastic optical fibers are strengthening mode coupling. We show that, solving the Langevin equation (stochastic differential equation), one can treat a mode coupling in heated multimode step-index plastic optical fibers, which is a result of fiber’s intrinsic random perturbations.