Multi-Core Fiber Technology for SDM: Coupling Mechanisms and Design

Coupling mechanisms and design issues in multi-core fibers (MCFs) for space division multiplexing are described in this paper. For uncoupled MCFs, a design procedure that considers random structural perturbations and effects of correlation length and birefringence beat length on inter-core crosstalk are presented based on coupled mode theory. Further, for coupled MCFs, a numerical estimation method of modal dispersion is described, and the method to enhance random mode mixing is presented.