Submillimeter-wave power measurements with commercial infra-red detectors

In this paper, we present studies of the capability of commercially available infra-red detectors at submillimeter-wavelengths. The detection is based on pyro- and thermoelectric effects. These technologies have been developed to a mature level for applications in infra-red regime. The detectors are low-cost, compact, and robust - qualities that a typical submm-wave power detector does not possess. The IR detectors are not confined to be operated only in infra-red regime. The principle of power detection remains the same also at submm-wavelengths. Results of measurements at 625-814 GHz with commercial IR detectors compared to dedicated submm-wave power detectors are presented. Sensitivity and noise-equivalent power of the pyroelectric detector is estimated to be 600 V/W and 0.6 μW/Hz^1/2 at 784 GHz at 20-Hz chopper frequency.