Plasmon scattering from single subwavelength holes

5 pags, 4 figs. -- PACS numbers: 78.68.+m, 73.20.Mf, 73.50.BkWe map the complex electric fields associated with the scattering of surface plasmon polaritons by single subwavelength holes of different sizes in thick gold films. We identify and quantify the different modes associated with this event, including a radial surface wave with an angularly isotropic amplitude. This wave is shown to arise from the out-of-plane electric dipole induced in the hole, and we quantify the corresponding polarizability, which is in excellent agreement with electromagnetic theory. Time-resolved measurements reveal a time delay of 38±18fs between the surface plasmon polariton and the radial wave, which we attribute to the interaction with a broad hole resonance. © 2012 American Physical Society.This work is part of the research program of the Stichting voor Fundamenteel Onderzoek der Materie (FOM), which is financially supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). This work is supported by NanoNextNL of the Dutch ministry EL&I and 130 partners. F. J. G. d. A. acknowledges support from the Spanish MEC (MAT2010-14885 and Consolider NanoLight.es)