Superconducting submillimeter direct detector using high-frequency current noise

Kurzfassung

A new concept of a superconducting submillimeter detector is presented. The novel aspect is an implementation of electric noise, which generally hampers the performance of conventional detectors, as a physical quantity that itself senses radiation. The detector operates well below the superconducting transition temperature and utilizes radiation-induced changes in the current-dependence of high-frequency noise. Advantages of this approach are a high-frequency read-out avoiding flicker noise and a tuneable noise level that can be adjusted to a particular pre-amplifier. The detector is a nano-bridge made from a thin superconducting film. Radiation couples into the detector via a planar antenna. Predicted noise-equivalent power at 4 K is 10_-13 W Hz_-1/2 and is likely to improve at lower temperatures.