Formation of polarization-dependent optical vortex beams via an engineered microsphere

Abstract

In this work, we propose a method that can realize switchable spatial arrangement of the donut-shaped focusing beams through an engineered microsphere, tuned by changing the polarization state of an incident light. In this polarization-dependent light manipulation, the engineered microsphere is designed and fabricated by focused ion beam (FIB). We simulate and experimentally characterize the focus performance of the engineered microsphere. Under the light incidence with radial polarization, multiple focused donut beams are formed along optical axis. By adding an additional linear polarizer with a rotatable relative angle, the pair of donut beams can be re-arranged in the same transverse plane and stay close to each other. Experimental results and numerical simulation are in good agreement. Such tunable polarization-dependent micro-optics can be used for multiplane imaging applications. © 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement