Abstract
Structure examination, resistivity, and thermopower measurements were made on samples of Bi1.75Pb0.35 Sr2Ca2Cu3O (y) sintered for different time periods. Thermoelectric power of all samples was found to be positive and changes slightly with sintering time prolongation. The normal state resistivity was analyzed using only the equation rho(n) =rho(0)+aT which was found to be satisfactory. The superconducting fluctuation behavior has been investigated using the Aslamazov and Larkin (AL), Lawrence and Doniach (LD), and Varlamov and Livanov (VL) models. In agreement with the theoretical prediction, the ln(Delta sigma/sigma (300))-ln(epsilon) plots exhibited three different regions, namely critical, mean field, and short wave fluctuation regions. Some parameters such as critical exponents, zero temperature coherence length zeta(0), the interlayer spacing d, the interlayer coupling nu, and the Fermi energy E-F have been estimated. The effect of sintering time on such estimated parameters has been studied. The critical exponent lambda values have indicated dimensionality cross-over from 2D to 3D for all the investigated samples.