Transport, magnetic and structural properties oft10 gpb0 5sr2_ cecajcuoj, compounds

Resistivity, DC magnetization and xray diffraction measurements were perform on 6 sample with nominal compositionTlftsl'bil)SrJ.,CcICa;Cu3Oj, , with x =0.0, 0.1, 0.2, 0.3, 0.4 and O.S. As cerium content was increased, the transition temperature increased ii> to about 6 K when x0,1. The phase diagram of tlie onset transition temperature versus Co content reflects the expected behavior as the hole concentration in the CuO plane is expected to decrease with Increasing x, passing from nvcnlopcd through optimally doped to an underdosed state for higlicr values of Cc4f replacing Sr⁺ tons. Magnetization measurements at 4 K, in cyclic Held ±) Tesla, onhe other hutid, showed tliat the ct itic;il current density of the samples decreased as Cc content was increased for till values v. It also showed the existence of the superconducting phase up to x=O.S, which was not detectable by resistivity measurements. Xray diffraction measurements, indicate that Cc enters the structure of the Tl1223 plinst, and hence affect its superconducting properties as it changes tlic charge carrier concentration in the CuO planes.