Design of trench-nanopore-assisted double-clad weakly coupled few-mode fiber for short-haul mode division multiplexing.

In this paper, we present a novel design of trench-nanopore-assisted double-clad few-mode fiber, which can support 14 linearly polarized (LP) modes. The trench-nanopore structure is introduced to effectively split adjacent modes and decrease bending loss. We evaluate the impact of parameters on the effective modal index (n_eff), the minimum effective refractive index difference (minΔn_eff) and modal effective area (A_eff) by using the finite element. The bending loss and broadband performance of the entire C+L bands, including n_eff, Δn_eff, differential mode delay (DMD) and dispersion, are also investigated. The simulated results show that all modes supported by the designed fiber are completely separated with Δn_eff between adjacent modes larger than 6 × 10^–4 over the whole C+L-band. Bending loss is lower than 10⁻⁵ dB/m. The designed trench-nanopore-assisted fiber has the potential applications for short-haul mode division multiplexing systems to improve transmission capacity. [ABSTRACT FROM AUTHOR]