We experimentally demonstrate a novel, all-plasmonic nanoscopic cavity exhibiting Q-factors up to 200 at visible frequencies. The Fabry-Pérot type resonator uses tall metallic fins that reflect up to 98% of incident surface plasmon to concentrate light within a subwavelength cavity mode. High aspect ratio metal fins, constructed using lithography and electroplating, reduce surface plasmon scatt...

The Green’s-theorem integral equation formulation is employed to study numerically the coupling into surface plasmon polaritons by illuminating a finite metal grating with a Gaussian beam from the vacuum half-space above the metal surface. A flat surface impedance boundary condition is used to simplify the scattering integral equations. The grating coupler period is chosen so that the first dif...

Localized surface plasmon resonance (LSPR) is strongly associated with inelastic scattering of biochemical molecules near metal nanostructures, i.e., surface enhanced Raman scattering (SERS). Systematically exploration of the relationship between surface-enhanced Raman spectroscopy (SERS) and the plasmon resonance wavelength has been an experimental limitation due to the lack of reliable and tu...

Structuring metallic surfaces allows for the support of surface electromagnetic modes at frequencies which they would not be allowed smooth surfaces. These are called ``spoof plasmons'' because their similarity to plasmons that supported optical This article describes physics underlies behavior spoof and how these used in applications require manipulation fields below optical.