The Faraday effect in magnetized plasma has long been understood as a polarization rotation phenomenon caused by the different propagation speeds between left circularly-polarized (LCP) waves and right circularly-polarized (RCP) waves, within the framework of plane wave theory. Recently, waves with helical wavefronts have been gaining increasing attention both in laser plasma physics and magnetized plasma physics, where their exact eigenmodes were determined by two wavevectors. This work uncovers a counterintuitive magnetic splitting mechanism of circularly polarized (CP) light into vortex vector beams with different azimuthal modes in an axially magnetized plasma. Our rigorous analysis identifies that the exact vortex electromagnetic eigenmodes in axially magnetized plasma are cylindrical vector beams, where CP modes are the superpositions of these eigenmodes. The magnetic splitting phenomenon of the CP pulse is predicted and confirmed by the simulation. Analysis shows that a larger transverse wavenumber leads to a higher amplitude ratio, corresponding to the laser waist radius and azimuthal number. The present study supplements the fundamental plasma physics and might furnish potential applications in space plasma physics.
 

Faraday effect,Magnetic splitting,cylindrical vector beams,strong magnetic field,vortex light