Non-Zero Dispersion-Shifted Ring-Core Fiber Supporting 60 OAM Modes

Orbital angular momentum (OAM) modes have becoming more promising to further achieve higher spectral efficiency and data capacity in space-division-multiplexing (SDM) fiber communication systems. In this work, we design and optimize a graded-index non-zero dispersion-shifted ring-core fiber (GI-NZDSRF) to support OAM modes in fiber-based transmission system. A record high number of 60 OAM modes in the C band with <10 ps/nm/km chromatic dispersion (CD) is obtained. A low differential mode delay (DMD) (<5.11 ps/m) and a large effective mode area (>1418 μm
²
) of OAM modes are achieved by the designed fiber. Furthermore, the effects of fiber parameters on OAM modes are also investigated, including the index shape, doping concentration, central location, and half width of the high index region.