Nanofabrication Of Optical Functional Plasmonic Materials

Typically metals can be used as conductors in electronics or reflectors in optics,however, in recent years, the plasmon resonance effect which originates fromconduction electrons coupling with resonance light has attracted scientists’ attentionall over the world. When continuous noble metals resonated with light, there will bepropagating surface plasmon resonance (PSPR). If the noble metals werediscontinuous at nanometer level, it was called localized surface plasmon resonance(LSPR). While LSPR was under developing, so how to fabricate patterns on noblemetals surface has received more and more attention of scientists from various fields.Various types of nanostructures have been developed, such as sharp nanocone arrays,sharp metallic grooves and nanowedges, triangular nanoprisms, nanopins, nanocages,nanocubes, nanobars and nanocrescent arrays. Besides the above-mentioned structures,the nanocrescent structure has attracted a large amount of attention due to its specialstructural features and fine optical properties.In this paper, a method for fabricating nanocrescent structures is presented basedon a combination of colloidal lithography and parallel imprinting. There are severalbreakthroughs on our nanocrescent structures:1. The central angle of thenanocrescents could be adjusted in the range of0o–360o, by changing the tilt angleand azimuth angle of evaporation.2. This method provides a low-cost and highlyreproducible way to prepare complex nanostructure arrays.3. Because the texture ofPDMS film was soft, in theory the crescent pattern not only can be imprinted on theflat surface, but also can be imprinted on the curved surface. In this paper, we notonly fabricated gold nanocrescent on glass substrate, but also regulating the resonanceabsorption peak’s shift of gold particles monolayer, through polymer assisted regulation. The color of gold nanoparticles monolayer changes significantly afterheating and this change can be detected by naked eyes. By SEM characterization wefound that the gold nanoparticles auxiliary heating by polymer was uniform sphere.However, the gold nanoparticles were wormlike without auxiliary heating by polymer.It can be said that polymer assisted modulation of optical properties of goldnanoparticle monolayers have long-term significance.