Ring-based coil structure photonic crystal fiber for transmission of Orbital Angular Momentum with large bandwidth: Outline, investigation and analysis

Abstract A unique, spectacular design of Photonic Crystal Fiber (PCF) is discussed in this paper to introduce one of the highest numbers of Orbital Angular Momentum (OAM) modes for the very first time with a very large bandwidth of 1,900 nm. Three layers of convoluted coiled structure air cavities formed the cladding region. The optimal design of PCF is used to derive the OAM properties. Finite Element Method (FEM) is used to examine and calculate the fundamental optical characteristics. The result of simulation supports 56 OAM modes with flat dispersion variation. Most of the OAM modes for confinement loss are below 1 0 − 8 dB/m where the lowest value is 1.7407 × 10−11 dB/m at wavelength 1,100 nm for H E 11 , 1 mode. The non-linear coefficient and numerical aperture are lower than 4 W−1km−1 and 0.17, respectively. These splendid optical characteristics ensure the addressed design as a striking competitor for OAM transmission with large bandwidth and many other relevant optical communications. It can be used in long haul communication, encoding and Mode Division Multiplexing (MDM).