High temperature superconducting Josephson device and method for manufacturing the same

A high critical temperature superconducting Josephson device, comprising:

• a bicrystal substrate comprising a first single crystal substrate and a second single crystal substrate, end faces of said first single crystal substrate and said second single crystal having different crystal orientations and being joined to each other;
• a first superconducting electrode formed of a first film of a high critical temperature superconductor material and located on said first single crystal substrate;
• a second superconducting electrode formed of a second film of a high critical temperature superconductor material and located on said second single crystal substrate;
• a bridge formed of a third film of a high critical temperature superconductor material and located on said bicrystal substrate across a joint between said first and said second single crystal substrates, said bridge connecting said first electrode and said second electrode, said bridge comprising a first part formed on said first single crystal substrate and connected with said first electrode, a second part formed on said second single crystal substrate and connected with said second electrode, and a third part interposed between said first part and second part on said joint between said first and said second single crystal substrates;
• and
• a weak link comprising a conductive film formed on a portion of said bridge and having a conductivity less than that of said first superconducting electrode and less than that of said second superconducting electrode, said conductive film formed over said joint so as to extend across said third part of said first part to said second part of said bridge;
• wherein a superconductive path is formed from said first electrode to said second electrode via said first part of said bridge, said weak link and said second part of said bridge during a state in which said third part of said bridge is non-superconductive.