Mode coupling in glass optical fibers and liquid-core optical fibers by three methods

Abstract

© 2015 Elsevier Ltd. All rights reserved. We test Slemon and Wells's function and recently reported Hurand et al.'s (Appl. Opt., 50, 492-499, 2011) function for calculation of coupling characteristics in step-index optical fibers against experimental measurements and against calculations by a related method that is based on the power flow equation. Compared are the coupling length L<inf>c</inf> (which is the fiber length where the equilibrium mode distribution is achieved) and length z<inf>s</inf> (where steady-state distribution is achieved) in three step index glass optical fibers as well as a liquid core optical fiber. The two functions, while simpler to apply being just algebraic formulas, are less accurate over a wide range of numerical apertures. It is also shown that fibers with same coupling coefficient can have much different coupling characteristics.