Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1815332 | Physica B: Condensed Matter | 2007 | 4 Pages |
Abstract
We found that a mixture of materials Sr2YSbO6 insulator with YBa2Cu3O7-δ superconductor is a system where the particles of superconductor and insulator materials are found coexisting in a composite with two well-defined separate phases. Electrical transport properties and percolation behavior have been studied by electrical resistivity measurements at room temperature on several samples of composites with different vol% of YBa2Cu3O7-δ. Resistivity measurements agree with the equation which describes the conductivity in percolation theory. However, critical exponent t=6.65 is greater than universal value tâ¼2. Furthermore, there is a non-negligible conductivity below percolation threshold while it is expected to be zero in ideal percolative systems. Nevertheless, percolative behavior in this region was found and, critical exponent value s was determined to be s=0.75 in agreement with universal value.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
O. Ortiz-Diaz, D.A. LandÃnez Téllez, F. Pérez, H. Tovar, J. Roa-Rojas,