Polarization Conjugated-Phase Component for Sorting Efficiently Vector Beams by Polarization Topological Charge

Abstract

Polarization topological charge (PTC) of a vector beam can be defined as the repetition number of polarization state change along the azimuthal axis, with its sign standing for the rotating direction of the polarization. In this paper, we present a design for PTC sorting of vector beams with polarization conjugated-phase component (PCC). The components, made of birefringent crystals, can induce conjugated spatial phase modulations for the orthogonal polarizations. Our simulations show, using a pair of PCC with specific design in a 4-f optical system, the system focuses vector beam modes on the locations representing the PTC of corresponding mode, and sorts PTC with separation efficiency as high as 77%. Our designs have the potential applications in modal characterization, communication, encryption, and so on.

Keywords

• Demultiplexing
• Optical polarization
• Optical fiber communication
• Optical diffraction
• Laser modes
• Optical devices