Fabrication and properties of superconducting single crystal cross-(micro)whiskers junction

Superconducting single crystal Bi-2212 (micro)whiskers have been fabricated by annealing a glass Bi2Sr2Ca2Cu3Ox precursor. The Tc and Tzero of ∼20 mm long and 10-70 μm wide single crystal whiskers were found to be 85 K and 82 K, respectively. The critical current density Jctransport of the whiskers was calculated to be 1313 A cm-2 at 0 T and 10 K. Then, a couple of whiskers were placed cross-wise on the YSZ single crystal substrate and heat treated to form micro-scale junction. The I-V characteristics of the micro-junction at 10, 30 and 60 K were found to show a multiple branch structure and that confirms to a model based on intrinsic Josephson junction