An ultra-low-power multi-octave deep-cooled amplifier for superconducting single-photon detectors

A design of low-noise wide band (0.05...1 GHz) cooled videoamplifier for prospective terahertz-range single-photon superconducting nanowire detectors is reported. The amplifier differs from existing prototypes by reduced consumption power (4mW) and ability of direct integration with the primary superconducting transducer to prevent false triggering caused by reflected waves in the detector-amplifier transmission line. The absolute stability, low noise factor and back action make the amplifier suitable also for other radio astronomy and physical applications.