d-like Symmetry of the Order Parameter and Intrinsic Josephson Effects in Bi2212 Cross-Whisker Junctions

摘要

An intrinsic tunnel junction was made using two Bi-2212 single crystalwhiskers. The two whiskers with a cross-angle were overlaid at their c-planesand connected by annealing. The angular dependence of the critical currentdensity along the c-axis is of the d-wave symmetry. However, the angulardependence is much stronger than that of the conventional d-wave. Furthermore,the current vs. voltage characteristics of the cross-whiskers junctions show amultiple-branch structure at any cross-angle, indicating the formation of theintrinsic Josephson junction array.