Design and cross talk optimization in single-mode high-core count multicore fiber under limited cladding diameter

Abstract

To achieve the minimum cladding diameter (CD) at fixed cladding thickness (35 μm) in the trench-assisted (TA) homogeneous multicore fibers (MCFs), five different core structures have been proposed under the single-mode propagation condition. The high-core counts, up to 37 cores with dense hexagonal closed packing arrangement of homogeneous cores have been considered for the analysis. The expression for cross talk (XT) under bending and twisting conditions has been derived using conventional method. The influence of core pitch, fiber length, fiber bending, twisting, and trench depth has also been exhibited on the XT performance for fundamental (LP01) mode propagation. The optimal CD based on specific values of cladding thickness and core pitch has been estimated in all the respective core structures for the target XT value of < − 50 dB / 100 km. The dispersion properties have also been investigated for all the proposed core structure, which is obtained nearly as −6 ps / nm-km at operating wavelength of 1550 nm. Further, in anticipation of high transmission capacity, the 61-core TA MCF has been analyzed for the XT performance under the limited CD of 300 μm.