Non-zero dispersion-shifted fiber with 16 heterogeneous ring cores supporting orbital angular momentum modes

OAM modes can significantly increase the number of spatial channels due to their unique characteristics, offering great potential for applications in the field of space-division multiplexing. This work proposes a 16-core heterogeneous non-zero dispersion-shifted ring-core fiber, whose structure is optimized using a particle swarm optimization algorithm. The optimized fiber exhibits a chromatic dispersion ranging from 1 to 10 ps/nm/km in the C-band. The fiber comprises two types of heterogeneous cores, each supporting modes with an effective mode area greater than 94 μm 2 , and the difference in effective mode area for the same mode between different core types is less than 7 μm 2 . At a core pitch of 26 μm, the inter-core crosstalk for the HE 2,1 mode is -31.7 dB/100 km, and the critical bending radius is as low as 14 mm. The crosstalk can be further reduced through propagation direction interleaving technology. The results demonstrate that the proposed fiber achieves large effective area, low dispersion, and low crosstalk while exhibiting excellent bending resistance, making it suitable for high-capacity OAM space-division multiplexing transmission systems.