ROOM-TEMPERATURE TRANSPORT-PROPERTIES OF NEW BISRCACUO COMPOUNDS

New compounds belonging to the BiSrCaCuO cuprate family have been synt hesized by sequentially imposed layer epitaxy. The Cu/Ca ratio in thes e compounds is typically twice the value for conventional Bi2Sr2Can-1C unO2n+4. A second characteristic of the new compounds is a Bi deficien cy relative to conventional BSCCO. The room temperature electrical res istivity of these compounds reaches extremely low values, orders of ma gnitude below that of copper. Strongly non-linear I(V) characteristics of various forms are observed. Typical examples are described where t he Voltage dependence at the onset of measurable dissipation is either exponential or parabolic as a function of current intensity. Examples are also presented where I(V) exhibits an hysteretic behavior.