Wu, XS (reprint author), Nanjing Univ, Dept Phys, Natl Lab Solid State Microstruct, Inst Solid State Phys, Nanjing 210093, Peoples R China.
Polycrystallized Y1-xCaxBa1.9Nd0.1Cu3Oy (YCBNCO) compounds with x less than or equal to 0.40 were synthesized using standard solid state reaction technique. The structure for all samples was characterized by X-ray diffraction with Rietveld refinements. The transport properties for YCBNCO were measured by the standard four-probe method in the temperature range from 20 to 300 K. With the increase of Ca content, the variation of the superconducting transition temperature T-c can be divided into three regions: in the doping region I with x less than or equal to 0.10, T-c decreases sharply and linearly with x, which may relate to the competition between Ca2+ and Nd3+; in the region II with 0.10 < x < 0.25, T-c deviates the fitting line; and in region III with x greater than or equal to 0.25, T-c decreases slowly with increasing Ca content,which may relate to the formation of the Ca-rich phase. The dependence of resistivity on temperature, and the relation of the structural parameters versus the content of Ca were discussed. The Ca content dependence of the spin-gap opening temperatures in the normal state for YCBNCO was investigated. (C) 2003 Elsevier B.V. All rights reserved.
Wu, XS,Tan, WS,Xu, YM,et al. Structure and spin-gap in the normal state of Y1-xCaxBa1.9Nd0.1Cu3Oy cuprates[J]. PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS,2003,398(3-4):#REF!.
Wu, XS.,Tan, WS.,Xu, YM.,Zhang, EM.,Du, J.,...&Gao, J.(2003).Structure and spin-gap in the normal state of Y1-xCaxBa1.9Nd0.1Cu3Oy cuprates.PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS,398(3-4),#REF!.
Wu, XS,et al."Structure and spin-gap in the normal state of Y1-xCaxBa1.9Nd0.1Cu3Oy cuprates".PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS 398.3-4(2003):#REF!.