Spectral response of plasmon resonant nanoparticles with a non-regular shape

We study the plasmon resonances of 10 - 100 (nm) two-dimensional metal part icles with a non-regular shape. Movies illustrate the spectral response of such particles in the optical range. Contrary to particles with a simple sh ape (cylinder, ellipse) non-regular particles exhibit many distinct resonan ces ver a large spectral range. At resonance frequencies, extremely large e nhancements of the electromagnetic fields occur near the surface of the par ticle, with amplitudes several hundredfold that of the incident field. Impl ications of these str ng and localized fields for nano-optics and surface e nhanced Raman scattering (SERS) are also discussed. (C) 2000 Optical Societ y of America.