MEASUREMENTS OF THE THERMOELECTRIC COEFFICIENT OF COPPER-OXIDE SUPERCONDUCTORS - ABSENCE OF ORDER-PARAMETER FLUCTUATION EFFECTS

Measurements of the thermoelectric coefficient, L(T), of polycrystalli ne Bi1.5Pb0.5 Sr2Ca2Cu3Oy and Y1Ba2Cu3O7-delta samples are presented. The analysis confirms and extends our proposals that L(T) is not appre ciably affected by the presence of thermal fluctuations. In some sampl es, the thermoelectric power, S(T) curve presents an anomalous sharp p eak near the superconducting transition. This peak may easily be expla ined by the presence of small T-C-inhomogeneities, associated with sma ll oxygen content inhomogeneities.