This work presents a rectangular large core area (R-LCA) PCF with a cladding diameter of 125 µm, a pitch of 9 µm, and a hole diameter of 8 µm. The guided modes were obtained through numerical simulations using COMSOL Multiphysics. This R-LCA-PCF has the potential to be used for refractive index sensing.
Alves et al. (Mon,) studied this question.