Superconductivity Near 30K Without Copper: Ba sub (.6) K sub (.4) BiO sub 3 Perovskite.

Here we report the results of experiments leading us to the single phase perovskite Ba sub (.6) K sub (.4) BiO (3-delta) which has magnetically determined onset temperature of 29.8K; a T sub c considerably higher than that of conventional superconductors and surpassed only by copper containing compounds. Superconductivity in this compound occurs within the framework of a three-dimensionally connected bismuth oxygen array. These results suggest that further research toward exploring the limiting T sub c 's for bismuth oxide based high temperature superconductors might be quite fruitful.