Abstract
We have fabricated thin-film do SQUIDs (Superconducting QUantum Interference Devices) incorporating Nb/AlOxide/Nb tunnel junctions. The spectral density of the voltage noise, Sv, of stripline SQUIDs is characterized between 1 Hz and 2000 Hz. In this frequency range, S v is proportional to the square of the responsivity (ϖV/ϖΦ) over a significant range of bias conditions with an unusual frequency dependence. In a 7 pH SQZIK the spectral density of the flux noise, S Φ, at 1 Hz is less than 10 −11 Φ 0 2/Hz, where Φ 0 ≡ h/2 e. The observed noise does not appear to be environmental; also, it is independent of the value of the junction shunt resistance and whether the stripline material is a Pbln alloy or Nb. Subject to the constraint of a constant product of the junction area, critical current density, and SQUID self-inductance in the SQUIDs studied, S Φ is inversely proportional to the junction area.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
