An energy converter employing plasmons. In a specific embodiment, a receiver receives a first type of energy or signal and provides one or more plasmons in response thereto. A detector is coupled to the receiver. The detector converts the one or more plasmons into a second type of energy or signal. In a more specific embodiment, the first type of energy or signal includes incident electromagnetic energy, such as visible, infrared, or ultraviolet radiation. The second type of energy or signal includes an electrical signal. The receiver includes a conductor grating that is coupled to a dielectric material. Examples of the detector includes a pn-junction and an interfacial bandgap junction. The receiver and the detector are coupled so that the one or more plasmons form a plasma wave as they travel from the receiver to the detector.