Vortex phases and c-axis correlation in as-grown and heavy ion irradiated Bi<SUB>2</SUB>Sr<SUB>2</SUB>Ca<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>10+&#948;</SUB> tapes: a flux transformer experiment

We report transport measurements on as-grown and heavy ion irradiated tapes of (Bi-Pb)2 Sr2 Ca2Cu3 O10+&#948; (Bi-2223) superconductor performed using a flux transformer (FT) geometry. A two level resistive transition is identified. Our studies suggest the existence of three vortex liquid regimes with different c -axis correlation of the unirradiated tape. These observations are compared with reported FT measurements on YBa2 Cu3 O7 and Bi2 Sr2 CaCu2 O8 superconductors. The system behaves like twinned YBCO due to the presence of growth related defects and misorientation between the crystallites Columnar defects (CDs) renormalize the inherent anisotropy of Bi-2223 further and a highly c -axis correlated vortex liquid is formed in samples with the CDs