Tunneling spectroscopy in Ba1−xKxBiO3

✍ Scribed by R.C. Dynes; F. Sharifi; A. Pargellis; E.S. Hellman; B. Miller; E. Hartford; J. Rosamilia

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 480 KB
• Volume: 185-189
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(91)91978-d

✦ Synopsis

Bat_xKxBiO3 is to date the highest Tc member of a class of superconductors which, it could be argued, belong in the same class of materials as the copper oxides. While there are striking differences between the bismuthates and the cuprates, there are some similarities. In this paper, we will report the .r~_ults of our tunneling measurements on BKBO. The determination of the energy gap in this material suggests that it is a relatively weakly coupled BCS superconductor -a similar conclusion is reached in the sister compound BaPbl_xBixO3. These results are substantially different from similar measurements in the cuprates. In addition, we have studied the background tur.:.eling conductance in four of the compounds in this class (BaPbO3, BaPbt.xSbxO3, BaPbl.xBixO3 and Bal_xKxBiO3) and find a remarkable correlation between the strength of the linear conductance and the superconducting transition temperature. Finally, the Josephson tunneling in these compounds will be discussed.