Abstract: An optical amplifier suitable for coherently amplifying surface plasmon-polariton waves with high gain and low noise over visible and infrared wavelengths. The optical amplifier is comprised of a thin strip of material having a complex permittivity with a negative real part, in contact on at least one side with an optical gain medium, where the strip has finite width and thickness such that optical radiation couples to the strip and propagates along its length as a surface plasmon-polariton wave. The surface plasmon-polariton amplifier can also be incorporated into a resonant cavity to form a plasmon-polariton laser.

Abstract: An optical amplifier suitable for coherently amplifying surface plasmon-polariton waves with high gain and low noise over visible and infrared wavelengths. The optical amplifier is comprised of a thin strip of material having a complex permittivity with a negative real part, in contact on at least one side with an optical gain medium, where the strip has finite width and thickness such that optical radiation couples to the strip and propagates along its length as a surface plasmon-polariton wave. The surface plasmon-polariton amplifier can also be incorporated into a resonant cavity to form a plasmon-polariton laser.

Abstract: A waveguide structure comprises a thin strip of material having a relatively high free charge carrier density surrounded by material having a relatively low free charge carrier density. The width and thickness of the strip are dimensioned such that optical radiation having a wavelength in a predetermined range couples to the strip and propagates along its length as a plasmon-polariton wave. The device includes a waveguide heater for passing a current through the strip to heat it and the surrounding material, so as to vary propagation of the optical radiation, or means for monitoring propagation of the optical radiation to determine a change in temperature of the strip. Some embodiments provide both heating of the strip and monitoring of its temperature.