Analytical expressions for the crosstalk of super-modes in the tightly bounded multicore fibers

Abstract

In this paper, an analytical approach for the super-modes in the tightly bounded multicore fibers is proposed. The method considers deterministic and random inter-core coupling, and the analytical analysis is based on the ordinary differential equations (ODEs), which are derived from the stochastic differential equations (SDEs). It is theoretically found that the crosstalk level is directly proportional to the square of the ratio for the random inter-core coupling strength over the deterministic coupling strength, and is inversely proportional to the random coupling correlation length. The ODEs for the variance and the super-mode power correlations are also provided to further facilitate the analysis for the tightly bounded multicore fibers. Simple and explicit formulas for the super-mode crosstalk power and power covariance evaluation are provided in the weak super-mode crosstalk scenario.