IEEE 11- superconductors and microwaves


Superconductivity, along with other cryogenic
electronic technologies, can provide
microwave and millimeter-wave (mm-wave)
components, both passive and active, with
characteristics superior to what can be realized
using conventional room-temperature technologies
[1], [2]. Radio astronomers have been cooling their
receiver front ends to temperatures of 10 K and below
for more than 50 years whereas superconductor-insulator-
superconductor (SIS) devices cooled to near 4 K
have been used as the mixers and detectors of preference
for radio telescopes operating in the mm-wave
frequency range since the 1970s. Other cryogenic electronics
that date back to the 1960s include infrared focal
plane arrays that were operated at temperatures of
50–70 K whenever long wavelength operation and very
low noise are required. Although superconducting devices
(such as high Q-value cavities) have a long history
in high-energy physics (HEP) particle accelerators,
other applications have not found wide use. Several
factors have contributed to this situation including the
lack of maturity of some of these technologies.