The factors affecting the flux-to-voltage transfer function of the series-SQUID array with grain-boundary Josephson junctions were investigated. By using the proposed critical-current-modulation model, it is found that the voltage swing of the series-SQUID array is suppressed greatly by the spread in critical currents of Josephson junctions. For the inductance L = 80 pH and the logarithmic average critical current 2 Iave = 20 μA. of the component SQUID, the allowed spread in critical currents of Josephson junctions is 0.4 Iave to 2.2 Iave for achieving the low flux noise with the series SQUID array.
- Critical-current spread
- High-temperature superconductors
- Josephson junctions
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering