The specific heat anomaly of Bi2Sr2CaCu2O8+δ at Tc in dependence on the oxygen content

✍ Scribed by W. Schnelle; N. Knauf; J. Bock; E. Preisler; J. Hüdepohl

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 682 KB
• Volume: 209
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(93)90560-d

✦ Synopsis

Melt casting processed samples of Bi,Sr,CaCu,O,+d were prepared with oxygen contents ranging from kO.126 to 6=0.22 and characterized by electrical resistance and AC-susceptibility. The r, of this compound is shifted reversibly between 75 and 95 K by annealing in Ar and/or O2 atmospheres for various times. The anomalies of the specific heat at T, were measured with a resolution of AC/C-5x 10m4. They can be described by a superposition of a mean field step and a contribution due to strong, two-dimensional fluctuations.

By a fit of a model with 2D gaussian fluctuations to the specific heat near T, we estimate AC and the in-plane coherence length c,, (0) of the superconductor.