In this work, we present X-ray diffraction, Raman spectroscopy and magnetizations measurement of the system CaLaBaCu3-X(PO 4)XO7-δ with X=0.1, 0.3, 0.5 which is superconductor with the critical temperatures: Tc=20 K to X=0.1, Tc=14 K to X=0.3 and Tc=20 K to X=0.5. Samples were prepared by the solid-state reaction method under normal conditions of pressure and temperature, replacing 0.1, 0.3 and 0.5 of phosphate (PO4) 3- in the Cu(1) site of CaLaBaCu3O7-δ (La1113). The X-ray diffraction patterns revel the presence of BaCuO2 and CuO as secondary phases, BaCuO2 increases as phosphate increases in the samples. Rietveld refinements suggest orthorhombic crystalline structures, belonging to Pmmm spatial group, for all the samples; nevertheless there are variations in the cell parameters. Tc's were determinate by measurements of magnetization using a SQUID detection system, which indicate variation of Tc according with phosphate concentrations. An study by Raman spectroscopy is added. Finally, the chemical analysis by EDX of a scanning electronic microscope (Phillips XL30) indicates the appropriates amounts of phosphorus in the samples.
|Number of pages||5|
|Journal||Journal of Physics and Chemistry of Solids|
|State||Published - Jan 2006|
Bibliographical noteFunding Information:
This work was supported by the Universidad Nacional Mayor de San Marcos and its Superior Council of Research under contract NO. 041301021.
- A. Superconductors
- C. Raman spectroscopy
- C. X-ray diffraction