Effect of ZnO and Zn0,95Mn0,05O nano-particle inclusions on YBCO polycrystalline pinning properties

Abstract

The effect of nano-size ZnO or Zn0.95Mn0.05O (ZnMnO) addition on the microstructure and pinning properties of polycrystalline YBa2Cu3Oy (YBCO) was analyzed. Samples with nano-particles ZnO and Zn0.95Mn005O addition were synthesized by solid state reaction. Microstructure investigation by transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDS), critical current density dependence on applied magnetic field Jc (B) and electrical resistivity as a function of temperature ρ(T) were carried out to evaluate the relative performance of samples. Using the right amount of ZnO or Zn0.95Mn0.05O addition (0.2 wt.%), the flux pinning ability of YBCO has been enhanced. The best flux pinning was observed for Zn0.95Mn0.05O added sample. The flux pinning enhancement suggests magnetic interaction of pinning centers via vortices. © 2010 IOP Publishing Ltd.