M. Savović, B. Drljača, K. Aidinis, X. Deng, S. Savović
University of Kragujevac,
Serbia
Keywords: communications, multicore optical fibers, photonic crystal fiber, angular division multiplexing, sensors
Summary:
We introduce a novel approach to angular division multiplexing (ADM) using a newly designed multimode step-index (SI) silica multicore photonic crystal fiber (MC-PCF) featuring nine cores arranged in a hexagonal pattern. Instead of relying on material doping, which can introduce limitations and complexity, MC PCFs investigated in this work utilize the geometry of the air holes to control essential characteristics like the effective index contrast, modal dispersion, birefringence, and mode confinement. By adjusting parameters such as hole diameter and lattice pitch, one can tailor the fiber’s performance without altering the underlying silica composition. This degree of design freedom enables the creation of specialized fibers with complex core profiles, all while maintaining the inherent low loss and high purity of silica. To assess the impact of mode coupling on the ability to support two-, three- and four-channel ADM in each core, we solve the power flow equation and analyze the results. Our numerical simulations demonstrate that mode coupling plays a crucial role in limiting the effective fiber length for which ADM can be implemented with minimal crosstalk between adjacent angular optical channels within each of the nine cores. Each core of the newly proposed SI silica MC-PCF with nine cores can support two, three, and four angular channels with minimal crosstalk over distances up to 100, 30 and 10 m, respectively. Such detailed characterization will be essential for optimizing the modal performance and capacity of MC-PCF-based communication systems. Furthermore, the proposed approach offers angularly distributed sensing channels within each of the nine cores, enabling high-density, crosstalk-free spatially distributed and multi-analyte detection in a single fiber.