Measurement and simulation of the voltage-flux transfer function of SQUID arrays

We measured the V-/spl Phi/ of 100-element SQUID arrays and compared them to simulations. Two SQUID inductances, 13 pH and 5 pH were studied. The change of voltage modulation depth per /spl Phi//sub 0/ in a 5 pH SQUID array was faster than that in a 13 pH SQUID array due to larger effective area variations. The effect of magnetic field uniformity on the SQUID arrays output was also studied. We found that a non-uniform magnetic field had the effect of reducing the output voltage and periodicity in V-/spl Phi/ for a SQUID array with high flux bias.<
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