Self-organized nanograting: a plasmonic dichroic polarizer

Self-organized periodic nanostructures (SPNs) have attracted significant interest due to their unique optical properties. This article examines SPNs as dichroic polarizers that selectively transmit or absorb light based on polarization. We explore the underlying mechanisms, fabrication techniques, and potential applications of SPNs. The SPNs are generated in a photosensitive AgCl-Ag thin film, by irradiating it with a linearly polarized He-Ne laser beam. The relocation of Ag nanoparticles into the minima of the interference pattern results in the formation of SPNs.The chain-like arrangement of metallic granular lines of silver clusters displays dichroism, polarizing the probe beam. The quality of the produced plasmonic dichroic polarizer depends on the exposure time. Thus, one can consider the exposure time as a control parameter for the quality of the product. Our research indicates dichroic polarizers, created using elliptically or circularly polarized laser beams, are less effective than those produced by a linearly polarized laser beam. The plasmonic dichroic polarizer, made using a linearly polarized laser beam with a 30-min exposure time, exhibited the highest polarization percentage (approximately 70%) for the probe beam at a wavelength of 525 nm, which is very close to the surface plasmon resonance peak of silver nanoparticles placed on AgCl substrate.