Evidence suggesting superconductivity at 250 k in a sequentially deposited cuprate film.

An artificial cuprate compound belonging to the BiSrCaCuO family with eight adjacent sequetially imposed layer epitaxy. This compound undergoes a five order of magnitude resistivity drop with an onset near 280 kelvin and an offset at 250 kelvin. It exhibits a diamagnetic variation of susceptibility and magnetization below 290 kelvin. Additional observed features, such as strongly nonlinear conductivity, suggests superconductivity as a plausible explanation of the properties of this compound.