Antenna-coupled microbolometers for passive THz direct detection imaging arrays

In the recent years, millimetre wave and THz imaging have received a vast amount of interest due to the interesting possibilities and applications that imaging at these frequencies could enable. Many of the applications that have generated substantial interest (such as stand-off concealed weapons detection) often require exquisite sensitivity, while a low system cost is required. In this paper we discuss one potential candidate for affordable imaging arrays: an antenna-coupled superconducting microbolometer. We show that these devices possess capabilities that are hard to meet with other passive detection schemes. While refrigeration to cryogenic temperatures is required for maximum performance, we show that the devices can be operated within a cryogen-free refrigerator that allows for turn-key operation. Comparison with other detectors is presented