Three-dimensional plasmonic nanoclusters driven by co-assembly of thermo-plasmonic nanoparticles and colloidal quantum dots
Won‐Geun Kim, Vasanthan Devaraj, Younghwan Yang, Jong‐Min Lee, Ji Tae Kim, Jin‐Woo Oh, Junsuk Rho
Abstract
Metallic nanoparticles that support localized surface plasmons have emerged as fundamental iconic building blocks for nanoscale photonics. Self-assembled clustering of plasmonic nanoparticles with controlled near-field interactions offers an interesting novel route to manipulate the electromagnetic fields at a subwavelength scale. Various bottom-up, self-assembly manners have been successfully devised to build plasmonic nanoparticle clusters displaying attractive optical properties. However, the incapability to configure on-demand architectures limits its practical reliability uses for scalable nanophotonic devices. Furthermore, a critical challenge has been addressing the accurate positioning of functional nanoparticles, including catalytic nanoparticles, dielectric nanoparticles, and quantum dots (QDs) in the clustered plasmonic hotspots. This work proposes a micropipette-based self-assembly method to fabricate three-dimensional architectures composed of colloidal clusters. The heterogeneous colloidal clusters comprising metallic nanoparticles and QDs are fabricated in one step by the micropipette-based self-assembly method. A plasmonic clustered pillar embedding QDs exhibited excellent photoluminescence characteristics compared to a collapsed pillar. The experimental and theoretical demonstration of the localized surface plasmon resonance and thermo-plasmonic properties of the colloidal clusters was performed.