title: Lattice modes mediate radiative coupling in metamaterial arrays.
abstract: We show that a resonant response with very high quality factors can be achieved in periodic metamaterials by radiatively coupling their structural elements. The coupling is mediated by lattice modes and can be efficiently controlled by tuning the lattice periodicity. Using a recently developed terahertz (THz) near-field imaging technique and conventional far-field spectroscopy together with numerical simulations we pinpoint the underlying mechanisms. In the strong coupling regimes we identify avoided crossings between the plasmonic eigenmodes and the diffractive lattice modes.
authors.affiliation: Freiburg Materials Research Center, University of Freiburg, Freiburg, Germany. andreas.bitzer@gmail.com
authors.forename: Andreas
authors.initials: A
authors.lastname: Bitzer
authors.forename: Jan
authors.initials: J
authors.lastname: Wallauer
authors.forename: Hanspeter
authors.initials: H
authors.lastname: Helm
authors.forename: Hannes
authors.initials: H
authors.lastname: Merbold
authors.forename: Thomas
authors.initials: T
authors.lastname: Feurer
authors.forename: Markus
authors.initials: M
authors.lastname: Walther
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design; D008422:Materials Testing; D008962:Models, Theoretical; D055095:Optics and Photonics; D020349:Surface Plasmon Resonance; D055053:Terahertz Radiation; D055068:Terahertz Spectroscopy / Q000295:instrumentation / Q000379:methods*