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.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering