Integer- and fractional-order cylindrical vector beam generation via self-assembled dichroic dye thin films

Integer- and fractional-order cylindrical vector beams have attracted widespread attention due to their wide range of tunable parameters and unique optical properties. In this paper, we propose a method for multi-order vector polarization control using self-assembled monolayers composed of dichroic dye molecules. The surface energy distribution of the liquid crystal polymer substrate is precisely controlled by dynamic laser direct writing lithography technology, driving the dichroic dye molecules to form a spatially continuous angular gradient micro-nanostructure. The results show that the single control element can realize integer- and fractional-order precise continuous cylindrical vector beam polarization state generation. The polarization modulation characteristics of cylindrical vector beams with different polarization orders were studied to reveal the changes in its polarization states during rotation, providing a method for high-precision optical control and measurement. This single polarization element has advantages in system miniaturization, process compatibility, and functional scalability, which are conducive to the flexible design and development of compact and high-precision optical systems.