| 摘要 |
PURPOSE:To extend the margin of operation, and to simplify circuit constitution by connecting a first strip line to a second strip line through a Josephson tunnel junction having parallel relationship with a resistor and controlling the characteristics of the Josephson tunnel junction by injecting quasi-particles to the first strip line. CONSTITUTION:Nb thin-films are evaporated onto a sapphire substrate 10, and a pair of strip lines 12, 14 divided on their midways are formed through dry etching. An electrode 20 for injection quasi-particles crossing at right angles with the strip line 12 is shaped onto the narrow section 16 of the strip line 12. The electrode 20 for injecting quasi-particles is constituted by an Nb evaporating film, and a tunnel barrier 22 is composed of a plasma oxide film in Nb, thus forming a tunnel type Josephson junction. An insulating layer 24 is shaped and windows are formed onto the strip lines 12, 14, and an upper electrode 28 is shaped so as to fill the windows. Current-voltage characteristics between the strip lines 12, 14 are controlled by changing injection currents Ic from the electrode 20 for injecting quasi-particles. |
