title: Unveiling nanometer scale extinction and scattering phenomena through combined electron energy loss spectroscopy and cathodoluminescence measurements.
abstract: Plasmon modes of the exact same individual gold nanoprisms are investigated through combined nanometer-resolved electron energy-loss spectroscopy (EELS) and cathodoluminescence (CL) measurements. We show that CL only probes the radiative modes, in contrast to EELS, which additionally reveals dark modes. The combination of both techniques on the same particles thus provides complementary information and also demonstrates that although the radiative modes give rise to very similar spatial distributions when probed by EELS or CL, their resonant energies appear to be different. We trace this phenomenon back to plasmon dissipation, which affects in different ways the plasmon signatures probed by these techniques. Our experiments are in agreement with electromagnetic numerical simulations and can be further interpreted within the framework of a quasistatic analytical model. We therefore demonstrate that CL and EELS are closely related to optical scattering and extinction, respectively, with the addition of nanometer spatial resolution.
authors.affiliation: Laboratoire de Physique des Solides CNRS/UMR8502, Bâtiment 510, University Paris-Sud, Orsay 91405, France.
authors.forename: Arthur
authors.initials: A
authors.lastname: Losquin
authors.forename: Luiz F
authors.initials: LF
authors.lastname: Zagonel
authors.forename: Viktor
authors.initials: V
authors.lastname: Myroshnychenko
authors.forename: Benito
authors.initials: B
authors.lastname: Rodríguez-González
authors.forename: Marcel
authors.initials: M
authors.lastname: Tencé
authors.forename: Leonardo
authors.initials: L
authors.lastname: Scarabelli
authors.forename: Jens
authors.initials: J
authors.lastname: Förstner
authors.forename: Luis M
authors.initials: LM
authors.lastname: Liz-Marzán
authors.forename: F Javier
authors.initials: FJ
authors.lastname: García de Abajo
authors.forename: Odile
authors.initials: O
authors.lastname: Stéphan
authors.forename: Mathieu
authors.initials: M
authors.lastname: Kociak
keywords: bright and dark modes; cathodoluminescence; electron energy loss spectroscopy; light scattering; nanooptics; plasmonics