The trends of the reflectance spectra indicate that the localized surface plasmon modes can be spatially controlled by manipulating geometric parameters, namely the lattice constants of the array. The larger the lattice constants, the lower the frequencies of the LSP modes (note the red shift in the middle of the above image).

To study more of the modulated LSP modes, the researchers meshed the complex domains into simple geometries and applied a finite element method based on the FEMLEB code. Satisfactory agreement between the experimental observations and numerical results was obtained.

The team's array structures were fabricated using well established silicon technology and are reproducible. The implementation of exquisite designs will allow more efficient optical devices to be realized in the future.

The researchers presented their work in Nanotechnology.