Thermoelectric power studies on the BPSCCO system with silver addition

✍ Scribed by R. Rajput; Y.S. Reddy; R.G. Sharma; G.V. Subbarao; D. Kumar

• Book ID: 103946848
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 558 KB
• Volume: 213
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(93)90779-p

✦ Synopsis

The effect of silver addition on the superconducting properties (resistance and thermoelectric power) of the BiL6Pbo.,SrL6Ca2Cu3Oy superconductor has been studied for silver concentrations of 0, 5, 10, 20 and 50 wt.%. Silver is found to be nonreactive in so far as the onset Tc is found to remain unchanged at 1 l0 K. Silver, however, diffuses through the grain boundaries of the rather low-density, 2223 material weakening the intcrgrain coupling. T~o(zero resistivity transition) is thus reduced with the addition of silver. The normal state thermoelectric power (TEP) of these specimens has been fitted to a formula derived from marginal Fermi liquid hypothesis. The normal state value of TEP decreases with increasing silver concentration. To(zero TEP temperature) is almost the same for all these specimens and is higher than T~o, confirming a lower percolation threshold for TEP than the percolation threshold for conductance.