Voltage-Tunable Surface-Plasmon Band-Pass Optical Filters

Voltage-tunable optical band-pass filters based on surface plasmon waves have been proposed. These filters would function at both visible and infrared wavelengths. Whereas liquid-crystal tunable optical filters now on the market exhibit efficiencies of 20 percent or less, theoretical calculations predict that the efficiencies of the proposed tunable surface-plasmon filters could exceed 60 percent in some cases.