Homogeneous and heterogeneous multi-core fibers

Reduction of inter-core crosstalk in uncoupled multi-core fibers (MCFs) is the most critical issue for long-haul space division multiplexing transmission. In homogeneous MCFs, the crosstalk is degraded as increasing a bending radius. On the other hand, in heterogeneous MCFs, the crosstalk can be drastically reduced when a bending radius is larger than a specific value. Required coupling coefficient and propagation constant difference between neighboring cores as well as allowable outer cladding diameter and assumed bending radii range are important fiber design parameters for maximizing a relative core density in a MCF.