Complex Susceptibility of Single Crystal YBa₂Cu₃O_7-x (I)

Abstract

Superconducting transions of single-crystal YBa₂Cu₃O_7-x, thin films (100-6000 Å) and bulk specimen (1×1×0.5 mm³), were investigated in terms of complex susceptibility. Thin films measured in a magnetic field perpendicular to the film plane exhibited a characteristic field-amplitude dependence, i.e., for higher amplitude, the transition curve shifts to lower temperatures. The bulk specimen showed different features for a magnetic field parallel and perpendicular to the c planes. Some qualitative discussion is given.