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Anomalies of electrical properties of Sm-cuprate oxides substituted with yttrium and iron oxides at low temperatures

  • A. M. Samy
Testing And Evaluation
  • 37 Downloads

Abstract

Samples of Sm2-xRxCuO4 (R=Y and Fe), for x=0.0 and 0.05, were prepared by standard solid-state reactions. The lattice parameters of the single-phase cuprates increased for the altered samples. The samples were studied by differential scanning calorimetry, scanning electron microscopy, electrical resistivity, and thermoelectric power measurements. The effect of substitution was found to increase compound stability, decrease the electrical resistivity, and change the sign of the thermoelectric power. The anisotropy field due to apical oxygen in the unaltered sample was not found.

Keywords

electrical resistivity low temperatures Sm-cuprate oxides substitution thermal analysis thermoelectric power 

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Copyright information

© ASM International 2004

Authors and Affiliations

  • A. M. Samy
    • 1
  1. 1.Physics DepartmentAin Shams UniversityAbbassia, CairoEgypt

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