The bipolaron model in transport properties of YBa2Cu3Oy superconductor prepared by adding Pr2Co7 magnetic nanoparticles

Abstract

Samples with the addition of ferromagnetic nanoparticles of Pr₂Co₇ on YBa₂Cu₃O_y (YBCO) polycrystalline superconductor were prepared by the standard solid state reaction method. The analysis of x-ray diffraction patterns by Rietveld refinement indicates orthorhombique to tetragonal phase transformation and oxygen rate reduction from x=0.3% of Pr₂Co₇ content. Resistivity at room temperature increases as Pr₂Co₇ content increases. The normal state resistivity versus temperature was analyzed properly by the bipolaron model. It suggested the increase of mobile charge localization with Pr₂Co₇ content.

Keywords: Pr₂Co₇ ferromagnetic nanoparticles, high temperature superconductor, bipolaron model, localization of mobile charge