Study on the direct current characteristics of DC-SQUID series array

Abstract

BackgroundThe direct current superconducting quantum interference device (DC-SQUID) series array can be used as the second-stage amplifier of two stage DC-SQUID amplifier, or it can be used independently as readout device of Transition Edge Sensor (TES) detectors.PurposeThis study aims to establish a direct current relationship equation for exploring the DC characteristics of DC-SQUID series array.MethodsBased on the Josephson junction RSJ (Resistively Shunted Junction) mode, the direct current relationship equation was established. By solving the equivalent Foucault-Planck equation, the analytical expression under the influence of Gaussian white noise was obtained. Data on DC-SQUID series array were collected by high-precision electronics system, and experimental data were used to verify the accuracy of the equation.Results & ConclusionsThe DC circuit model and I-V relationship equation are established successfully. The influence of Gaussian white noise on the I-V curve is obtained. Experimental results show that the equations and models obtained in this paper are consistent with actual measurement results, and can be used for theoretical research.

Keywords

• squid
• josephson junction
• rsj model
• gaussian white noise