Thermoelectric properties of Bi-2223 superconductors at different conditions of sintering

Structural examination and thermoelectric power measurement are made on Bi1.75Pb0.35Sr2Ca2Cu3O10 samples sintered at different conditions. Thermoelectric power of all samples was found to be positive and it increases almost linearly with the decrease of temperature up to similar to 140 K, before falling to zero at T-co. However, the thermoelectric power changes slightly with increasing sintering temperature and time. The normal state results are analyzed in terms of a two-band model with an additional linear part T. The effects of sintering temperature and time on the parameters related to this model have been investigated.