Specific-heat of Na0.35CoO2 · 1.3H2O: Effects of sample age and pair breaking on two-gap superconductivity

✍ Scribed by N.E. Phillips; N. Oeschler; R.A. Fisher; J.E. Gordon; M.-L. Foo; R.J. Cava

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 152 KB
• Volume: 460-462
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2007.03.039

✦ Synopsis

Specific-heat measurements on Na 0.35 CoO 2 AE 1.3H 2 O show an evolution of the superconductivity, and its ultimate disappearance, with increasing sample age. An increase in pair breaking action, which occurs preferentially in an electron band with a small energy-gap, produces a shift in the relative contributions of two electron bands to the superconducting condensation. The similarity of the time scale for these changes to that recently reported for structural changes suggests a relation between the two effects and a basis for understanding the sample dependence of the properties of this material in general.