Magnetic dynamic hysteresis of a resistively shunted Josephson-junction array

The magnetization curves of a slablike uniform Josephson-junction array with resistive shunts are calculated from the dc and ac Josephson equations and the gauge-invariant phase difference. The parameters are chosen in accord with actual values for high-Tc superconductors (HTSC's). With decreasing sweep rate of the applied field, the result changes from a complete shielding to one approaching the envelope of the static magnetization curve, which is oscillatory and amplitude modulated. At certain intermediate sweeping rates the curves are critical-state-like. However, since these rates are a few orders of magnitude higher than those used in conventional experiments, the intergranular critical state shown in HTSC's cannot be modeled by such a uniform array. © 1994 The American Physical Society.