SIMULTANEOUS MEASUREMENT OF THERMAL-DIFFUSIVITY AND CONDUCTIVITY APPLIED TO BI-2223 CERAMIC SUPERCONDUCTORS

A method to measure the thermal diffusivity alpha and the conductivity kappa under an identical experimental setup has been developed and alpha and kappa of Bi-2223 oxide superconductor have been measured quasi-simultaneously. The results are analyzed on the basis of the BRT and Tewordt-Wolkhausen theory. The simultaneous measurement makes it possible to estimate the specific heat C and the Debye temperature THETA(D), as well as to separate the electron and phonon contributions to the diffusivity. The simultaneous measurement also provides a useful check on the reliability and the consistency of the analyses.