Laser-Controlled Growth of Plasmonic Gold Nanoparticles in PMMA Films for High-Resolution Optical Applications

High Resolution Image Download MS PowerPoint Slide The growing demand for portable electronics has driven advancements in micro- and nanoscale technologies. In this regard, plasmonic nanomaterials are particularly notable for their capacity to manipulate surface plasmons, enabling applications in super-resolution microscopy, optical nanosensors, cancer therapy, and high-resolution displays, among other fields. This work aims to control the size, concentration, density, and shape anisotropy of gold nanoparticles (AuNPs) while generating plasmonic platforms in poly(methyl methacrylate) (PMMA) films, controlling the laser power and translation speed during the direct laser writing technique. The nucleation and growth processes of AuNPs in PMMA films were explained using the laser-induced plasma classical model. Using a computational method based on the Mie-Gans approach, we identified nanoparticles with diameters ranging from 2 to 30 nm, concentrations varying from 0.9 μM to 1.9 mM, aspect ratio values between 1.1 and 1.5, and density like the bulk gold and plasmonic microstructures with widths spanning from 5 to 70 μm. Additionally, areas of the film with the highest nanoparticle density were mapped using rhodamine B fluorescence, which varied according to laser power. The results demonstrate that gold nanoparticles can be generated with high precision in polymers at a micrometer resolution with high chemical stability, making this technique versatile and cost-effective compared to traditional methods.