title: Dirac spectra and edge states in honeycomb plasmonic lattices.
abstract: We study theoretically the dispersion of plasmonic honeycomb lattices and find Dirac spectra for both dipole and quadrupole modes. Zigzag edge states derived from Dirac points are found in ribbons of these honeycomb plasmonic lattices. The zigzag edge states for out-of-plane dipole modes are closely analogous to the electronic ones in graphene nanoribbons. The edge states for in-plane dipole modes and quadrupole modes, however, have rather unique characters due to the vector nature of the plasmonic excitations. The conditions for the existence of plasmonic edge states are derived analytically.
authors.affiliation: Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: Dezhuan
authors.initials: D
authors.lastname: Han
authors.forename: Yun
authors.initials: Y
authors.lastname: Lai
authors.forename: Jian
authors.initials: J
authors.lastname: Zi
authors.forename: Zhao-Qing
authors.initials: ZQ
authors.lastname: Zhang
authors.forename: C T
authors.initials: CT
authors.lastname: Chan
mesh_terms: D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D020349:Surface Plasmon Resonance