Plasmonic Nanodisk Dimers and Cusp Nanostructures: Fabrication Using Self-Assembled Colloidal Doublets

We report a combination of bottom-up and top-down methods to fabricate nanodisk dimer structures (two nanodisks separated by small gap) over a large area with good plasmonic tunability and reasonable yield. We use “Salting Out-Quenching” (SQ), a bottom-up technique that takes advantage of temporal changing of colloidal forces, to synthesize colloidal doublets from polystyrene (PS) singlets and use them as templates for top-down fabrication of nanodisk dimer structures. In addition to nanodisk dimers, cusp nanostructures with sharp tips, i.e., two nanoholes in thin film with a separation smaller than their diameter can be fabricated by simple alterations in our method. Compared to single nanohole structures, cusp nanostructures exhibit both large transmission and magnitudes with significantly larger electric field intensity. Our method has the advantages of being rapid, scalable, inexpensive, and highly geometrically tunable.  In this talk we discuss the method for fabricating the nanoparticle doublets, and show their use in rapidly forming plasmonic structures.