Surface shape resonances of ridges on a thin film
Department of Physics and Astronomy, University of Western Ontario London, Ontario N6A 3K7, Canada
2 Departamento de Física, Universidade Federal do Ceará, Campus do Pici, Centro de Ciências, Caixa Postal 6030, 60455-760 Fortaleza, Ceará, Brasil
Revised: 6 July 1999
Published online: 15 February 2000
The spectrum of surface shape resonances associated with a finite number of ridges on one interface of an otherwise plane film is calculated. The frequencies are obtained numerically by solving the homogeneous integral equations which describe the electrostatic field in the vicinity of a surface defect. The calculations are performed for a surface with ridges with Gaussian, Lorentzian and sinusoidal profiles. The results show a strong dependence of the localized plasmon frequencies on the surface profile, on the distance between the ridges, and on the thickness of the film.
PACS: 73.20.Mf – Collective excitations (including plasmons and other charge density excitations) / 78.66.Bz – Metals and metallic alloys
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000