Study of current peaks in DC SQUID with integrated coupling coil

The mechanism and the damping condition are investigated for the resonant peak in the current-voltage characteristics of a DC superconducting quantum interference device (SQUID) coupled to an integrated multiturn input coil. It is experimentally confirmed that the resonant voltage, V/sub r/, depends on parameters of the coupling structure. The V/sub r/ and peak height are calculated based on an RF admittance and a balance equation for incident and dissipated powers in them SQUID. The analytical results agree qualitatively with experimental ones. A simple analytical formula for the damping condition is derived.<
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