Electromagnetic Field Enhancement for Wedge-Shaped Metal Nanostructures

Abstract

The role of localized surface plasmon resonances near the surface of a silver or gold wedge is discussed based on quasistatic theory. Strongly enhanced electromagnetic field intensities at moderate distances of 1 nm from the wedge are found by manipulating morphology and dielectric environment. The theory also shows that wedge structures can have high enhancements over a broad range of wavelengths, which is of relevance to surface-enhanced Raman scattering and tip-enhanced Raman scattering measurements and for improving plasmon enhanced photovoltaic devices.