Quantitate evaluation of the thermoelectric power of (Bi,Pb)2 Sr2CaCu2O8+δ from the experimentally determined electronic structure

Energy-momentum (ε-k→) dispersion of the overdoped (Bi,Pb)2Sr2CaCu2O8+δ with the superconducting transition temperature of 66 K was determined by the high-resolution angle resolved photoemission spectroscopy (ARPES). Bilayer-splitting caused by the two CuO2 planes in the basis was clearly observed in the present ARPES measurements. Spectral conductivity σ(ε) was calculated from the determined ε(k→) by taking the bilayer splitting into account with employing the Boltzmann transport equation. The calculated thermoelectric power S(T) form thus determined σ(ε) reproduced extremely well the observed one, strongly indicating the important role of the electronic structure on the temperature dependence of S(T) in the cuprate superconductors. The bilayer-splitting certainly provides a finite contribution to the temperature dependence of S(T) but it is too trivial to significantly affect the strong hole-concentration dependence of S(T)