Current states of a doubly connected superconductor with film bridges

Abstract

Transport current distribution in the branches of a doubly connected superconductor in the form of a thin-film high-inductance circuit with two bridges of different width in the branches was measured. For the transport current lower than the sum of critical currents of the bridges, its distribution was found to exhibit an anomalous behavior upon reaching the critical current of one of the bridges. For a fixed value of the transport current through the circuit higher than the sum of critical currents of the bridges, low-frequency continuous harmonic voltage self-oscillations together with synchronous current self-oscillations appeared in the circuit branches. The mechanism responsible for the onset of the self-oscillations is discussed.