Propagation of surface plasmons on Ag and Cu extended one-dimensional arrays on silicon substrates

Propagating surface plasmon waves can be supported by Cu and Ag periodic array, or grating, structures on silicon substrates. The plasmon dispersion characteristics, such as group velocity and bandgap associated with these structures are measured experimentally. In the infrared region of the spectrum (1.3-1.6 mu m) the properties of surface plasmons supported by these Ag and Cu periodic structures are virtually indistinguishable. The plasmon dispersion can be modified by varying either the grating period or the plasmon order. The plasmonic bandgap for this array geometry increases with increasing plasmon order.