Ba/sub 1-X/K/sub X/BiO/sub 3/ grain boundary junctions prepared on SrTiO/sub 3/ bicrystal substrates

We succeeded in the fabrication of Ba/sub 1-X/K/sub X/BiO/sub 3/ artificial grain boundary junctions prepared on SrTiO/sub 3/ bicrystal substrates. These junctions showed the Josephson current and the energy gap structure in the I-V characteristics. In a magnetic field, the critical current was modulated and the I/sub c/-B curve showed a clear Fraunhofer pattern. Fiske steps were also observed in the I-V characteristics. In the radiation of 10.5 GHz microwaves, Shapiro steps were observed.<
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