Abstract: To obtain a superconducting driver circuit which can obtain an output voltage of several millvolts or above, can use a DC power source as a driving power source, can form no capacitance between it and a ground plane, and has a small occupation area, the superconducting driver circuit is constructed by superconducting flux quantum interference devices (SQUIDs) each constructing a closed loop having as components two superconducting junctions and an inductor. The SQUIDs share the inductors and are connected in series in three or more stages.

Abstract: At least two ramp-edge-structure Josephson junctions having different critical current densities to one another are provided on a substrate.

Abstract: The invention relates to a technique for forming a thin film of good quality on a base substance via an intermediate layer. Such a film formation technique is suitably applicable to formation of an oxide high-temperature superconductor thin film usable for a superconducting wire material, a superconducting device or the like. In the method of forming a thin film on a base substance via an intermediate layer, an interface energy Ea at an interface A between the base substance and the intermediate layer, an interface energy Eb at an interface B between the intermediate layer and the thin film, and an interface energy Ec at an interface C between the base substance and the thin film in a state where the intermediate layer is omitted are calculated, and then a substance for the intermediate layer is selected so as to satisfy conditions of Ea<Ec and Eb<Ec.

Abstract: To provide a planarization method which does not depend upon the size and the density of a wiring pattern and in which a reliable wiring system and a Josephson device can be formed and wiring structure, an insulation layer is planarized by forming a reversal pattern mask of wiring and selectively removing the insulation layer on the wiring.

Abstract: The present invention relates to a method of preparing an oxide superconducting film, the method includes reacting a metal acetate containing metal M selected from the group consisting of lanthanum, neodymium and samarium with fluorocarboxylic acid having not less than three carbon atoms, reacting barium acetate with fluorocarboxylic acid having two carbon atoms, reacting copper acetate with fluorocarboxylic acid having not less than two carbon atoms, respectively, followed by refining reaction products, dissolving the reaction products in methanol such that a molar ratio of the metal M, barium and copper is 1:2:3 to prepare a coating solution, and coating a substrate with the coating solution to form a gel film, followed by calcining and firing the gel film to prepare an oxide superconducting film.

Abstract: A superconducting system that includes an interface circuit capable of making the best use of a high-speed superconducting circuit and a high-speed semiconductor circuit. A multi-chip module in which an Nb superconducting circuit having josephson junctions formed by the use of Nb and an oxide high-temperature superconducting latch interface circuit having josephson junctions formed by the use of an oxide high-temperature superconductor are connected is located in a low temperature environment kept at 4.2 K. The oxide high-temperature superconducting latch interface circuit is connected to a high-speed semiconductor amplifier and a signal outputted from the Nb superconducting circuit is transmitted to the high-speed semiconductor amplifier.

Abstract: There is provided is a method of manufacturing a superconductor layer, including preparing a coating solution by dissolving trifluoroacetates of at least one metal selected from the group consisting of yttrium and lanthanoids, barium, and copper in a solvent, coating a main surface of a substrate with the coating solution to form a coating film, subjecting the coating film to a calcining process in an atmosphere containing oxygen, and subjecting the coating film after the calcining process to a firing process in an atmosphere containing water vapor at a temperature higher than that at the calcining process. The calcining process is carried out such that the coating film after the calcining process and before the firing process have an average CuO particle diameter equal to or less than 25 nm.

Abstract: There is established a superconducting magnet made of a high-temperature bulk superconductor and capable of trapping a high magnetic field with ease and stably. The superconducting magnet made of the high-temperature bulk superconductor, for use by trapping a magnetic field, is made of the bulk superconductor provided with an artificial hole, a low melting metal impregnated into, and filling up at least the artificial hole, and a heat conducting metal material embedded with portions of the high-temperature bulk superconductor, impregnated with, and filled with the low melting metal. The superconducting magnet can be produced by a process comprising the steps of providing the artificial hole in the high-temperature bulk superconductor, disposing the heat conducting metal material in at least the artificial hole, applying a process of impregnating and filling up at least the artificial hole with the low melting metal, and subsequently, executing a process of magnetizing.

Abstract: The present invention provides a method for joining an RE123 oxide superconductor matrix obtained by a melt process by the use of a solder material. The (110) plane of an RE123 oxide superconductor matrix obtained by a melt process is used as the plane to be joined, a solder material composed of an RE123 oxide superconductor having a lower melting point than the above-mentioned RE123 oxide superconductor is interposed between the planes to be joined, and this solder material is melted and then solidified to form a joining layer, thereby joining the matrices. The solder material can be a sinter, a melt-processed material, a powder, a slurry, or a molded powder.

Abstract: A Josephson junction having a barrier layer sandwiched by two superconductors wherein the superconductors include one or more elements selected from the group of Y, La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu, one or more elements selected from the group of Ba, Sr and Ca, and Cu and oxygen, wherein the two superconductors each include at least five elements with compositions different from each other, or the barrier layer (5) includes one or more elements selected from the group of La, Nd, Sm and Eu, and one or more elements selected from the group of Y, Gd, Dy, Ho, Er, Tm, Yb and Lu.

Abstract: A metal substrate for an oxide superconducting wire, which comprises a polycrystalline metal substrate with a rolled aggregate structure having a {100} plane which is parallel to the rolled surface and a <001> axis which is parallel to the rolling direction, and an oxide crystal layer comprising an oxide of the polycrystalline metal and formed on a surface of the polycrystalline metal substrate, wherein at least 90% of grain boundaries in the oxide crystal layer have an inclination of 10° or less, and at least 90% of the {100} plane of the oxide crystal layer make an angle of 10° or less with the surface of the polycrystalline metal substrate.

Abstract: The present invention relates to an MgB2-based superconductor that is easy to manufacture and well suited to mass production, and that exhibits excellent superconducting characteristics (such as a high critical current density) while still retaining the high critical temperature characteristics of MgB2. A powder mixture of magnesium, boron, and titanium is pressed into a pellet, and this product is sintered under an atmospheric pressure and other conditions (preferably at 600° C. or higher) to manufacture an MgB2-based superconductor in which titanium and/or a titanium compound are dispersed in polycrystalline MgB2. The composition of the MgB2-based superconductor is preferably adjusted to have an atomic ratio of Mg:B:Ti=x:2:y, 0.7<x<1.2 and 0.05<y<0.3, and more preferably 0.07<y<0.2, by adjusting the amounts in which the raw materials are added.

Abstract: In a sampler for use in measuring a waveform of an electric signal, a measurement target current is given as the electric signal to a sampler chip 11 and is also used to produce a trigger current Itr for determining measurement timing on the sampler chip. A comparator 20 compares a sum of a feedback current, a current derived from the measurement target current, and the trigger current Itr with a threshold value to produce an SFQ pulse when the sum exceeds the threshold value. The SFQ pulse produced by the comparator is observed or counted for a predetermined duration to measure the waveform of the electric signal.

Abstract: A circuit includes a latch circuit including a Josephson junction and configured to perform a latch operation based on a hysteresis characteristic in response to a single flux quantum, a load circuit including load inductance and load resistance and coupled to an output of the latch circuit, and a reset circuit provided between the output of the latch circuit and the load circuit and configured to reset the latch circuit a predetermined time after the latch operation by the latch circuit, wherein the Josephson junction is driven by a direct current.

Abstract: An aqueous solution of mixed metal acetate including one kind or more of element selected from lanthanide series and yttrium, barium and copper is mixed with trifluoroacetic acid to prepare a solution of mixed metal trifluoroacetate. From a solution of mixed metal trifluoroacetate obtained thus, purified mixed metal trifluoroacetate of which total content of water and acetic acid is 2% by weight or less is prepared. With purified mixed metal trifluoroacetate, an oxide superconductor of excellent performance may be prepared.

Abstract: There is provided is a method of manufacturing a superconductor layer, including preparing a coating solution by dissolving trifluoroacetates of at least one metal selected from the group consisting of yttrium and lanthanoids, barium, and copper in a solvent, coating a main surface of a substrate with the coating solution to form a coating film, subjecting the coating film to a calcining process in an atmosphere containing oxygen, and subjecting the coating film after the calcining process to a firing process in an atmosphere containing water vapor at a temperature higher than that at the calcining process. The calcining process is carried out such that the coating film after the calcining process and before the firing process have an average CuO particle diameter equal to or less than 25 nm.

Abstract: A method of fabricating a Josephson device includes the steps of forming a first superconducting layer and forming a second superconducting layer to form a Josephson junction therebetween, wherein the step of forming the second superconducting layer includes the steps of conducting a first step of forming the second superconducting layer with improved uniformity and conducting a second step of forming the second superconducting layer on the second superconducting layer formed in the first step with improved film quality.

Abstract: The invention is intended to establish means for manufacturing MB2 single crystals and to provide a useful superconductive material (wire rod and so forth) taking advantage of anisotropic superconductive properties thereof. A mixed raw material of Mg and B or a precursor containing MgB2 crystallites, obtained by causing reaction of the mixed raw material of Mg and B, kept in contact with hexagonal boron nitride (hBN), is held at a high temperature in the range of 1300 to 1700° C. and under a high pressure in the range of 3 to 6 GPa to cause reaction for forming an intermediate product, thereby growing the MB2 single crystals having anisotropic superconductive properties via the intermediate product.

Abstract: An oxide superconductor of the present invention characterized in that it comprises: a substrate 1 made of metals having a high melting temperature; at least one oxide intermediate layer 2 and 3 which is formed on at least one surface of the substrate 1; and a thick film oxide superconductor layer 5 which is formed on the oxide intermediate layer 2 and 3 the liquid phase epitaxial method in which the substrate 1 provided with the oxide intermediate layer 2 and 3 is put into a solution 7 containing the elements comprising an oxide superconductor layer, and is then pulled out from the solution 7.

Abstract: An Hg- or Nd-based oxide superconductor comprises Ba as a constituent element and has a content of carbon as an impurity at a level of not greater than 2.0 atomic % whereby the oxide superconductor stably shows high superconducting characteristics without causing degradation with time. For its production, BaO, which has a reduced content of carbon impurity of 0.5% or below, is provided as a feed stock for Ba, and the starting materials are mixed and processed in a dry atmosphere wherein an amount of a carbon-containing gas is suppressed to a certain level, thereby obtaining the oxide superconductor.