High-Temperature Superconductivity in the BaPb 1-x Bi x O 3 System

Phases of the type BaPb1-xBix03 have been prepared for the first time. These phases all have perovskite related structures, and superconductivity was observed over the range x ≅0.05–0.3. The highest critical temperature is 13 K which is exceptionally high for an oxide and is much higher than that previously observed for any superconductor not containing a transition element. Semiconducting behavior is observed from x = 1 to about 0.35.