Measurements of the thermoelectric coefficient of copper oxide superconductors: Absence of order parameter fluctuation effects

Abstract

Measurements of the thermoelectric coefficient, L(T), of polycrystalline Bi 1.5Pb 0.5Sr 2Ca 2Cu 3O y and Y 1Ba 2Cu 3O 7−δ samples are presented. The analysis confirms and extends our proposals that L(T) is not appreciably affected by the presence of thermal fluctuations. In some samples, the thermoelectric power, S(T) curve presents an anomalous sharp peak near the superconducting transition. This peak may easily be explained by the presence of small T c-inhomogeneities, associated with small oxygen content inhomogeneities.