Numerical Study of Air-Core Ring Fibers with Lattice Cladding Supporting OAM Modes

This paper presents a numerical investigation of orbital angular momentum (OAM) modes in an air-core ring fiber incorporating air holes in the outer region of the ring forming the cladding structure. The eigenmodes are computed using the two-dimensional Helmholtz equation. It is demonstrated that the proposed design can support multiple stable OAM modes. The analysis includes detailed calculations of these modes' intensity and phase distributions. The results provide valuable insights into the design and fabrication of ring-core fibers for OAM-based quantum technology applications. Given its ability to support multiple distinct OAM modes, the proposed structure represents a promising design for successful physical fabrication.