Josephson - device, consisting of a josephson - by means of gear structure, which is suitable for a superconductor.

摘要

PURPOSE:To form a Josephson junction at a designated position with excellent reproducibility, by forming crystal discontinuity part arranged on a crystal substrate or a crystal film, a superconductor film grown on the crystal substrate or the crystal film, and grain boundary in the superconductor film on the crystal discontinuity part. CONSTITUTION:By focused ion beam method, gold ions are implanted in a part of strontium titanate substrate 1 where a Josephson element is to be formed. As the result of gold ion implantation, crystal structure of a part of the strontium titanate substrate is destroyed, and a discontinuity part of crystal is formed. By heating the strontium titanate substrate 1, and vapor-depositing yttrium barium copper oxide, superconductor electrodes 3, 4 are formed. Crystal orientation of film of the superconductor electrodes 3, 4 coincides with that of the strontium titanate base substrate, and C-axis becomes perpendicular to the surface. On the boundary of the superconductor 3, 4, crystal grain boundary 5 is formed at the upper position of the discontinuity part of the base. Then the electrodes are worked in desired forms, and necessary wiring is made up.