Formation of triplet and quadruplet plasmonic nanoarray templates by holographic lithography

Here, we extend the utility of holographic lithography to fabricate plasmonic multi-nanoparticle array templates with triplet and quadruplet symmetries. We describe how to systematically design such higher-order symmetries based on sub-lattice decomposition. Basic design rules and examples how to create twin, triplet, and quadruplet features are discussed. We also verify experimentally that these plasmonic templates can be fabricated featuring high filling fractions, up to four nanogaps, and defined electric field orientations. These results open up possibilities to fabricate multi-nanoparticle arrays at wafer scale with high-throughput as required for sensing and other emerging topics in nanoplasmonics.