Heterodyning far-infrared light using coherent photovoltaic effect

Summary form only given. There is great interest in development of a sensitive low-noise detector in the far-infrared (FIR) (10-100 /spl mu/m) range. The progress is impeded by a large dark current and associated thermal noise in the detectors, which significantly reduces their detectability. Detectability can be improved in the coherent or heterodyne schemes, where the sensitivity can be pushed to its quantum limit. Heterodyne detection in the 10.6-/spl mu/m range had been successfully implemented in quantum-well intersubband detectors (QWIPs). Therefore quite an effort has been directed toward development of the efficient local oscillators in the FIR range.