Modeling of the forming and propagation of optical vortex beams emitted by microring resonators

Subject of study. Microring resonators with a radiation-emitting diffraction grating formed by periodic holes on their surface are investigated. Aim of study . The aim of this study is to develop mathematical models for the emission and spatial radiation distribution of the optical vortex beams carrying orbital angular momentum, produced by microring resonators. Method . The process of optical beam radiation from a microring resonator is described using the general theory of electromagnetic wave scattering by dielectric inhomogeneities in the Rayleigh approximation. Optical vortex beam forming is considered in terms of the vector representation of electromagnetic fields based on the Kirchhoff–Helmholtz integral theorem. Numerical simulations were performed in the Ansys Lumerical software environment. Main results . Analytical expressions have been derived to determine the spatial distribution of the electric field and the energy flux density emitted by a microring resonator depending on the configuration of the resonator and the parameters of the periodic holes on its surface, as well as the region of the maximum energy flux density, depending on the topological charge of the generated optical vortex beam. To verify and confirm the accuracy of the second part of the mathematical model, additional numerical simulations were performed in the Ansys Lumerical environment. Practical significance. The findings of the study can be utilized to enhance the efficiency of communication channels and optimize them in promising optical information technologies.