Mode coupling in bent and twisted step-index plastic-clad silica fibers

Abstract

© 2020 Astro Ltd. The state of mode coupling in bent and twisted step-index plastic-clad silica fibers is investigated in this article by the numerical solving of the time-independent power flow equation. The coupling length L c at which the equilibrium mode distribution is achieved and the length z s of the fiber required for achieving the steady-state mode distribution are obtained. It was found that the bent and twisted step-index plastic-clad silica fiber investigated in this work shows a much stronger mode coupling than the straight plastic-clad silica fiber. As a result, the coupling lengths where equilibrium mode distribution is achieved, and the lengths of fiber required for achieving a steady-state mode distribution for bent and twisted fibers, are much shorter than corresponding lengths for straight fibers.