TRANSPORT, STRUCTURAL, AND MAGNETIC-PROPERTIES OF THE SINGLE-COPPER-OXYGEN LAYER BI2SR2-XLAXCUOY SYSTEM

The Bi2Sr2-xLaxCuO6+y system was studied in the regime 0.3 less-than-o r-equal-to x less-than-or-equal-to 1.0. Measurements of the magnetic s usceptibility, electrical resistivity, superconducting transition temp erature, crystal structure via neutron and X-ray diffraction, and oxyg en concentration y are presented. We find that stable single-phase spe cimens can be prepared in the range 0. 3 < x less-than-or-equal-to 1.0 and that y increases linearly with x. The critical temperature for su perconductivity T(c) passes through a maximum as a function of x which is found to be dependent on y. Similarities between our results and t hose on other high-temperature superconductors are drawn.