STUDIES ON BA1-XKXBIO3 SINGLE-CRYSTALS BY TUNNELING SPECTROSCOPY

Superconducting gap structure of Ba1-xKxBiO3 single crystals is studie d by means of electron tunneling spectroscopy. Dependencies of superco nducting gap structure on temperature and external magnetic field are simultaneously investigated for the really same junction. From the num erical analysis of experimental results with simple tunneling model, i t was found that the observed feature of superconducting gap can be qu alitatively understood in the framework of BCS theory. However, depend ence of magnetic field suggested that the dirty-limit model is not sui table for Ba1-xKxBiO3.