title: Multidimensional Hybridization of Dark Surface Plasmons.
abstract: Synthetic three-dimensional (3D) nanoarchitectures are providing more control over light-matter interactions and rapidly progressing photonic-based technology. These applications often utilize the strong synergy between electromagnetic fields and surface plasmons (SPs) in metallic nanostructures. However, many of the SP interactions hosted by complex 3D nanostructures are poorly understood because they involve dark hybridized states that are typically undetectable with far-field optical spectroscopy. Here, we use experimental and theoretical electron energy loss spectroscopy to elucidate dark SPs and their interactions in layered metal-insulator-metal disc nanostructures. We go beyond the established dipole SP hybridization analysis by measuring breathing and multipolar SP hybridization. In addition, we reveal multidimensional SP hybridization that simultaneously utilizes in-plane and out-of-plane SP coupling. Near-field classic electrodynamics calculations provide excellent agreement with all experiments. These results advance the fundamental understanding of SP hybridization in 3D nanostructures and provide avenues to further tune the interaction between electromagnetic fields and matter.
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Andrew B
authors.identifier: 0000-0002-1772-6778
authors.initials: AB
authors.lastname: Yankovich
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Ruggero
authors.initials: R
authors.lastname: Verre
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Olsén
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Anton E O
authors.initials: AEO
authors.lastname: Persson
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Viet
authors.initials: V
authors.lastname: Trinh
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Dovner
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Käll
authors.affiliation: Department of Physics, Chalmers University of Technology , 41296 Gothenburg, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Olsson
keywords: dark surface plasmons; electron energy loss spectroscopy (EELS); layered nanoparticles; nanoplasmonics; plasmon hybridization