Numerical analysis of circular core shaped photonic crystal fiber for orbital angular momentum with efficient transmission

In this paper, a circular core shaped photonic crystal fiber (PCF) is proposed and the optical propagation characteristics are investigated and simulated by applying the finite element method (FEM) with the help of COMSOL Multiphysics software. The cladding of this PCF is composed of fused silica including a large center air-hole. The simulation process is performed within 1000–2000 nm wavelength. The raised PCF supports up to 38 OAM modes with larger bandwidth (1000 nm) as well as flat dispersion variations. The refractive index difference can exceed 10-4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ 10^{ - 4}$$\end{document} for each OAM mode. The confinement loss of this PCF remains low approximately around 10-9\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$10^{ - 9}$$\end{document} to 10-8\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$10^{ - 8}$$\end{document} dB/m, comparatively better the nonlinearity, the numerical aperture, and the dispersion variation evolves into smoother. So, all these optimizing optical properties prove that our designed PCF is a promising candidate for the OAM mode transmission and other relevant optical communications.