Gupta, Anurag ; Sedky, A. ; Narlikar, A. V. ; Singh, D. P. (2002) Effect of Ar heat treatment on oxygenated R1−xCaxBa2Cu3O7−δ (R=Y, Sm) superconductors Journal of Materials Science, 37 (8). pp. 1557-1560. ISSN 0022-2461
Full text not available from this repository.
Official URL: http://www.springerlink.com/content/qel1e5tg4hcr3e...
Related URL: http://dx.doi.org/10.1023/A:1014925020459
Abstract
The influence of heat treatment, at 450°C in Ar environment, on oxygenated (6.72<7−δ<6.93) samples of R1−xCaxBa2Cu3O7-δ (i.e. R(Ca)-123, with R=Y, Sm) with 0<x<0.3 has been investigated. Measurements of oxygen loss, normal state resistivity behaviour ρ(T), superconducting critical temperature Tc and transition widths reveal that Ar treatment effects both the series differently. The Sm(Ca)-123 samples, for all values of x, show a considerable loss of oxygen (Δδ(x)= 0.4 to 0.6) and decrease in Tc (ΔTc(x)= 35 to 55 K). Whereas, surprisingly, the Y(Ca)-123 samples show a much smaller loss of oxygen (Δδ(x)=0 to 0.3), along with a decrease in Tc for x<0.2 and an increase in it for x≥0.2. In particular, the x=0.3 sample shows a negligible change in oxygen content accompanied by an increase of 20 K in Tc. These and host of other observations suggest that the presence of Ca may influence the oxygen loss mechanism in these series.
Item Type: | Article |
---|---|
Source: | Copyright of this article belongs to Springer. |
ID Code: | 32332 |
Deposited On: | 25 Jun 2011 13:59 |
Last Modified: | 25 Jun 2011 13:59 |
Repository Staff Only: item control page