We report measurements of the thermoelectric power of the high-temperature Tl-Ca-Ba-Cu-O superconductor. The data indicate a transition which is centered at 118 ± 3 K, in agreement with magnetic measurements and published resistivity results. The thermoelectric power is positive and, aside from the high transition temperature, is remarkably similar in magnitude and temperature dependence to that of the rare-earth-based oxide superconductors which have been reported previously.

• Received 11 March 1988

DOI:https://doi.org/10.1103/PhysRevB.38.7064