Effect of synthesis process and substrate on electrical and thermal transport properties of Bi-2212

Resistivity, thermoelectric power, and thermal conductivity have been measured for a Bi-2212 system synthesized from a glassy precursor, either with a commercially Al2O3 substrate or with a homemade BaZrO3 substrate. Those measurements show that the BaZrO3 substrate gives better superconducting properties to the Bi-2212 than the Al2O3 substrate. The effect of (1.0 T) weak magnetic field has been searched for. The thermal magnetoconductivity and the contributions of the magnetic field to the thermoelectrical power are studied and compared through fine measurements. An electronic contribution seems to appear already well above the critical temperature and to exist up to 200 degrees K. The onset temperature is thus deduced.