caa a22 4500 44538123X CHVBK 20180317143018.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s10948-010-1007-2 doi (NATIONALLICENCE)springer-10.1007/s10948-010-1007-2 Excess Conductivity Studies in Zn0.95Mn0.05O and ZnO Added YBa2Cu3O y Superconductors [Elektronische Daten] [I. Bouchoucha, F. Ben Azzouz, M. Ben Salem] We report electrical conductivity fluctuation analyses on YBa2Cu3Oy (denoted as YBCO) granular samples added with nanosize ZnMnO (ZnMnO for brevity) and ZnO (30 nm) particles. Nanoparticles are added to the precursor powders during the final sintering cycle of a two-step preparation process. Phase analysis by X-ray diffraction and granular structure examination by transmission electron microscopy (TEM) were carried out. When ZnMnO and ZnO are added to the YBCO, the orthorhombic structure is maintained. TEM and energy dispersive X-ray spectroscopy analysis show the presence of inhomogeneities embedded in the superconducting matrix. The temperature dependence of electrical resistivity in zero magnetic field has been measured on free, 1 wt.% ZnMnO and 1 wt.% ZnO added samples and the effect of microscopic inhomogeneities in the paraconductivity region has been reported. Data about the dimensionality of the thermodynamic fluctuation are obtained by analyzing the excess of conductivity Δσ as a function of the reduced temperature $\varepsilon =\ln(\frac{T}{T_{c}^{mf}}-1)$ on the basis of the Aslamazov-Larkin theory. In the mean-field region a crossover from 3D to 2D was observed for each sample. 1D behavior of fluctuation conductivity was found at high temperatures (above the 2D regime) for nanoparticle added samples. The zero-temperature coherence length, the effective layer thickness of the two-dimensional system, the wire cross-sectional area for one-dimensional system, critical magnetic fields and critical current density are estimated. Superconducting parameters are affected by the nanoparticle additions. Springer Science+Business Media, LLC, 2010 YBCO superconductor nationallicence Excess conductivity nationallicence Nanometer (Zn,Mn)O addition nationallicence Critical parameters nationallicence Bouchoucha I. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut Ben Azzouz F. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut Ben Salem M. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut Journal of Superconductivity and Novel Magnetism Springer US; http://www.springer-ny.com 24/1-2(2011-01-01), 345-350 1557-1939 24:1-2<345 2011 24 10948 https://doi.org/10.1007/s10948-010-1007-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10948-010-1007-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bouchoucha I. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut NATIONALLICENCE 700 1- Ben Azzouz F. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut NATIONALLICENCE 700 1- Ben Salem M. L3M, Department of Physics, Faculty of Sciences of Bizerte, University of 7th November at Carthage, 7021, Zarzouna, Tunisia aut NATIONALLICENCE 773 0- Journal of Superconductivity and Novel Magnetism Springer US; http://www.springer-ny.com 24/1-2(2011-01-01), 345-350 1557-1939 24:1-2<345 2011 24 10948 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer