Room temperature transport properties of new BiSrCaCuO compounds

New compounds belonging to the BiSrCaCuO cuprate family have been synthesized by sequentially imposed layer epitaxy. The Cu/Ca ratio in these compounds is typically twice the value for conventional Bi2Sr2Can-1Cun+4. A second characteristic of the new compounds is a Bi deficiency relative to conventional BSCCO. The room temperature electrical resistivity of these compounds reaches extremely low values, orders of magnitude below that of copper. Strongly non-linear I(V) characteristics of various forms are observed; Typical examples are describes where the voltage dependence at the onset of measurable dissipation is either exponential or parabolic as a function of current intensity. Examples are also presented I(V) exhibits and hysteric behavior. (authors)