Abstract: A lanthanum aluminate (LaAlO3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also be used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: Compounds of the general formula A4MeSb3O12 wherein A is either barium (Ba) or strontium (Sr) and Me is an alkali metal ion selected from the group consisting of lithium (Li), sodium (Na) and potassium (K) have been prepared and included in high critical temperature thin film superconductors, ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Abstract: A lanthanum aluminate (LaAlO3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: A superconductor structure inclludes a substrate made from a temperature-resistant glass material, a buffer layer which has been deposited on the substrate, and a layer of a metal oxide high Tc superconductor material that has been deposited thereon. A glass material with a coefficient of thermal expansion of over 6·10−6 K−1 and a transformation temperature of over 550° C. is to be provided. At least a deposition process in which a maximum temperature is at most 100 K higher than the transformation temperature of the glass material is selected for the production of the structure. A current limiter device is also provided.

Abstract: A lanthanum aluminate (LaAlO3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: The invention provides an improved substrate for growing layers of oxide superconductor materials for use in high current engineering applications. The invention also provides superconducting laminates based on the inventive substrates, and processes for the manufacture thereof. The substrate includes an alloy layer that is formed of either a cube-textured FeNi alloy containing about 47% Ni to 58% Ni, or (b) a cube-texture Ni—Cu alloy in the composition range 41% Ni to 44% Ni. The substrate may further include an oxide buffer layer covering a surface of the alloy layer.

Abstract: A thin-film of a high temperature superconducting compound having the formula M1-xCuO2-y, where M is Ca, Sr, or Ba, or combinations thereof, x is 0.05 to 0.3, and x>y. The thin film has a Tc (zero resistivity) of about 40 K. Also disclosed is a method of producing the superconducting thin film.

Abstract: A clad superconductive wire or tape of an oxide superconductive material and a silver-copper alloy base containing 0.05-90 atomic % copper or a silver alloy. The silver-copper alloy base contains one or more elements selected from the group of Zr, Hf, Al, V, Nb and Ta in amounts of from 0.01-3 atomic %, or contains Au in amount of 0.01-10 atomic %. The silver alloy contains one or more elements selected from the group of Ti, Zr, Hf, V, Nb, Ta, Mg, Ca, Sr and Ba in amounts of from 0.01 to 3 atomic %, or one or more elements selected from the group of Au, Al, Ga, In and Sn in amounts of 0.05 to atomic %. The base material is filled with a Bi-containing oxide of Bi1PbuSrxCayCuzOw wherein u=0-0.3, X=0.8-1.2, y=0.2-1.2, and z=0.8-2.0, and processed to obtain a superconductive wire or tape having enhanced mechanical strength, superconductivity and plastic workability.

Abstract: A high temperature oxide superconductor is efficiently protected from the affects of water and acids by forming a passivation layer of a fluoride. The fluoride layer comprises a fluoride composed of one or more elements composing the oxide superconductor and/or one or more elements that can compose an oxide superconductor by replacing at least in part one or more elements composing the oxide superconductor.

Abstract: The invention relates to a layered structure with at least one epitaxial, non-c-axis oriented high Tc superconductor (HTSC) thin film with an approximately tetragonal structure, in which the thin film having an orientation (-1,0,1) is formed on a cubic or pseudocubic (1,0,3) NdGaO.sub.3 substrate.

Abstract: A novel ceramic substrate useful for the preparation of superconductors, said substrate having the formula Ba.sub.2 DyMO.sub.5.5 where M represents at least one of the metals Zr, Sn and Hf and a process for the preparation of said ceramic substrate, which comprises (i) Reacting salts of dysprosium, barium and Zr, Sn or Hf in an organic medium, (ii) Pressing the resultant mixture in the form of pellets, (iii) Calcining the pellets by heating at a temperature in the range of 1000 to 1200.degree. C., (iv) Repeating the calcination process for 30-45 h at temperature in the range of 1000-1200.degree. C. until a highly homogenous mixture is formed. (v) Grinding the calcined material and pelletising at a pressure in the range of 3 to 4 tons/cm.sup.2, (vi) Sintering the resultant product at a temperature in the range of 1200 to 1600.degree. C. for a period of 10 to 30 h, and then furnace cooled to room temperature.

Abstract: A novel ceramic substrate useful for the preparation of superconducting films, said substrate having the formula REBa.sub.2 MO.sub.6 where RE represents rare earth metals--Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and M represents metals Nb, Sb, Sn, Hf, Zr; and a process for the preparation of superconducting YBa.sub.2 Cu.sub.3 O.sub.7-.delta. thick films on new ceramic substrate.

Abstract: A lanthanum aluminate (LaAlO.sub.3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO.sub.3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: Compounds of the general formula A.sub.4 MeSb.sub.3 O.sub.12 wherein A is either barium (Ba) or strontium (Sr) and Me is an alkali metal ion selected from the group consisting of lithium (Li), sodium (Na) and potassium (K) have been prepared and included in high critical temperature thin film superconductors, ferroelectrics, pyroelectrics, piezoelectrics, and hybrid device structures.

Abstract: A superconducting garnet thin film system (10) is provided for high frequency microwave applications where a single crystal high temperature superconducting (HTSC) layer (18) is integrated with a garnet substrate (12). A first perovskite compound buffer layer (14) is epitaxially grown on an upper surface of the garnet substrate layer (12) and defines a lattice constant less than the lattice constant of the garnet substrate layer (12) with the first perovskite layer being aligned in a cube on cube parallel orientation with respect to the garnet substrate layer (12). A second perovskite layer (16) is epitaxially grown on an upper surface of the first perovskite layer (14) at an orientation of 45.degree. to first layer (14) and defines a lattice constant less than the lattice constant of the first perovskite layer.

Abstract: A method for the fabrication of active semiconductor and high-temperature superconducting device of the same substrate to form a monolithically integrated semiconductor-superconductor (MISS) structure is disclosed. A common insulating substrate, preferably sapphire or yttria-stabilized zirconia, is used for deposition of semiconductor and high-temperature superconductor substructures. Both substructures are capable of operation at a common temperature of at least 77 K. The separate semiconductor and superconductive regions may be electrically interconnected by normal metals, refractory metal silicides, or superconductors. Circuits and devices formed in the resulting MISS structures display operating characteristics which are equivalent to those of circuits and devices prepared on separate substrates.

Abstract: A superconductive composite member comprises a core of oxide ceramic superconducting material that is disposed in a metal envelope comprising a silver alloy which is hardenable by an oxide dispersion. Preferably, the silver alloy is an alloy of Ag--Mg--Ni, Ag--Mn--Ni or Ag--Al alloy which may also include one or more precious metal elements selected from a group consisting of Ru, Rh, Pd, Os, Ir, Pd and Au. The composite member is formed by introducing the superconductive material into the silver alloy envelope, cross section-reducing the assembly of the envelope and core and, subsequently, thermal treatment for the recovery and setting of the oxygen concentration.

Abstract: An a.c. cable has at least one cable core (15) with two concentric conductor arrangements (8, 9) used as forward and return conductors. At least one of the conductor arrangements (8, 9) contains a plurality of conductor layers (L.sub.j and L.sub.j ') made of stranded normally conducting or superconducting individual conductors (3). The individual conductors preferably feature high-T.sub.c superconducting materials. The wire angles (.alpha..sub.j, .alpha..sub.j ') in the individual conductor layers (L.sub.j and L.sub.j ') should be selected so as to minimize losses. A calculation formula for the wire angles (.alpha..sub.j, .alpha..sub.j ') is given for this purpose.

Abstract: A composite material is disclosed which includes a substrate, an oriented film provided on a surface of the substrate and formed of a crystal of a Y123 metal oxide of the formula LnBa.sub.2 Cu.sub.3 O.sub.y wherein Ln stands for Y or an element belonging to the lanthanoid and y is a number of 6-7, and a layer of a Y123 metal oxide of the formula LnBa.sub.2 Cu.sub.3 O.sub.y wherein Ln stands for Y or an element belonging to the lanthanoid and y is a number of 6-7 formed on the oriented film.

Abstract: Excellent films of a high Tc superconductor are easily produced on metal coated substrates at a temperature below 700.degree. C. These metal buffer films are made of Pt, Au, Ag, Pd, Ni or Ti. The film superconductivity is significantly improved by the metal buffer layer. Since it is easy to form this metal coating on a substrate, the invention can increase the potential number of usable substrates such as fibers, amorphous solids or semiconductors.

Abstract: A composite high Tc superconductor film is applied to a substrate, said film as applied having a thickness of at least 5000 Angstrom and an outer surface having an average roughness not exceeding 250 Angstrom.

Abstract: An oxide superconductor comprises a base material consisting of a single crystalline oxide, an oxide superconductor film consisting of a Y123 compound and formed on the single crystalline oxide base material, and a coating film consisting essentially of a Ba--Cu--O oxide and covering the surface of the oxide superconductor film, the coating film having a thermal expansion coefficient higher than that of the oxide superconductor film.

Abstract: A starting material which is converted to a continuous body of an oxide superconductor by a heat treatment is filled in a tubular Ag sheath member. The diameter of the filled member is reduced by extrusion to form a wire. The wire is subjected to a heat treatment so that the starting material inside the sheath member is converted to a continuous body of an oxide superconductor. A superconducting wire constituted by the sheath member and the oxide superconductor filled inside the sheath member is obtained. A superconducting coil can be obtained by winding the superconducting wire.

Abstract: A Josephson junction element having a substrate of a single crystal having a V-shaped notch formed in a surface of the substrate and a wiring pattern of an oxide superconductor formed on the surface of the substrate and crossing the notch to form a weak link region in the pattern at a position above the notch. The notch is defined by first and second walls joining with each other at the bottom of the notch and has first and second corners at which the first and second walls meet the surface of the substrate. The first and second corners have radii of curvature of 5-50 nm and 50-500 nm, respectively, provided that the difference in radius of curvature between the first and second corners is not smaller than 10 nm. The notch is formed by obliquely irradiating a predetermined portion of the substrate with a focused ion beam.

Abstract: A superconducting ceramic film is deposited on a substrate sputtering. In virtue of the low thermal conductivity of ceramic, a laser beam is radiated to the ceramic film in order to remove the irradiated portion by sublimation and produce a pattern on the ceramic film.

Abstract: A lanthanum aluminate (LaAlO.sub.3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO.sub.3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: A biaxially textured article includes a rolled and annealed, biaxially textured substrate of a metal having a face-centered cubic, body-centered cubic, or hexagonal close-packed crystalline structure; and an epitaxial superconductor or other device epitaxially deposited thereon.

Abstract: A superconducting article including a flexible polycrystalline metal substrate, a layer of an adhesion layer material upon the surface of the flexible polycrystalline metal substrate, a layer of a cubic oxide material upon the adhesion layer material, the first layer of cubic oxide material deposited by ion beam assisted deposition, a layer of a buffer material upon the ion beam assisted deposited cubic oxide material layer, and, a layer of YBCO upon the buffer material layer is provided and has demonstrated J.sub.c 's of 1.3.times.10.sup.6 A/cm.sup.2, and I.sub.c 's of 120 Amperes across a sample 1 cm wide.

Abstract: This invention permits superconducting ceramics, as well as other ceramic materials, to be spray deposited onto indefinitely large sheets of metallic substrate from a carboxylic acid salt solution. Elemental metal precursors of the superconductor are introduced into the solution as carboxylic acid salts. The deposit formed on the malleable metallic substrate is then thermomechanically calcined to form c-axis textured metal-superconductor composite sheet structures. These composite sheet structures can be formed by pressing together two ceramic-substrate structures, ceramic face-to-face, to form a metal-ceramic-metal sheet structure, or by overlaying a metal sheet over the deposited structure. Once the structure has been thermomechanically calcined, the c-axis of the superconductor is oriented parallel to the vector defining the plane of the metal sheet, i.e., perpendicular to the surface of the plane.

Abstract: Superconducting transition metal oxide films are provided which exhibit very high onsets of superconductivity and superconductivity at temperatures in excess of 40.degree. K. These films are produced by vapor deposition processes using pure metal sources for the metals in the superconducting compositions, where the metals include multi-valent nonmagnetic transition metals, rare earth elements and/or rare earth-like elements and alkaline earth elements. The substrate is exposed to oxygen during vapor deposition, and, after formation of the film, there is at least one annealing step in an oxygen ambient and slow cooling over several hours to room temperature. The substrates chosen are not critical as long as they are not adversely reactive with the superconducting oxide film. Transition metals include Cu, Ni, Ti and V, while the rare earth-like elements include Y, Sc and La. The alkaline earth elements include Ca, Ba and Sr.

Abstract: A novel ceramic substrate useful for the preparation of superconducting films, said substrate having the formula REBa.sub.2 MO.sub.6 where RE represents rare earth metals--Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and M represents metals Nb, Sb, Sn, Hf, Zr; and a process for the preparation of superconducting YBa.sub.2 Cu.sub.3 O.sub.7-.delta. thick films on new ceramic substrate.

Abstract: In order to provide a crystal oriented high quality thallium group superconducting wire having a high critical current density, thallium group superconducting film is formed on oxide single crystal fiber having plane facets and polygonal cross section in the thallium group superconducting wire, wherein c-axis of the thallium group superconducting film is oriented perpendicularly, and a- and b-axis are oriented in parallel to the longitudinal direction of the above fiber, respectively, and resulting to obtain a high quality thallium group superconducting wire with Jc of 10.sup.5 A/cm.sup.2 or more at 77K.

Abstract: A high critical temperature superconducting Josephson device includes a bicrystal substrate formed of a first single crystal substrate and a second single crystal substrate, with end faces of the first and second single crystal substrates 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 is located on the first single crystal substrate, whereas a second superconducting electrode formed of a second film of a high critical temperature superconductor material is located on the second single crystal substrate. A bridge is formed of a third film of a high critical temperature superconductor material and located on the bicrystal substrate across a joint between said first and said second single crystal substrates.

Abstract: A device with weak links (Josephson junctions) in a superconducting film has two single crystals connected through an interconnecting arrangement that may have one or more sublayers. At least two grain boundaries or at least one barrier are/is formed in the substrate.

Abstract: The present invention presents an electrostatic discharge and power surge protected circuit board (10) and method for providing an electrostatic discharge and power surge protected circuit board. The protected circuit board (10) includes temperature sensitive conducting material (14) and semiconductor circuit components (12). The temperature sensitive conducting material (14) has a critical current density, provides a high impedance when the critical current density is exceeded, and preferably comprises a high temperature superconductor. Preferably, the temperature sensitive conducting material (14) and the semiconductor circuit components (12) are coupled in series. In a method aspect of the present invention, an electrostatic discharge protected circuit board (10) is provided by providing a current carrying mechanism (16) on the circuit board (10), and coupling the current carrying mechanism (16) to temperature sensitive conducting material (14).

Abstract: Compounds of the general formula A.sub.2 MeSbO.sub.6 wherein A is either barium (Ba) or strontium (Sr) and Me is a non-magnetic ion selected from the group consisting of scandium (Sc), indium (In) and gallium (Ga) have been prepared and included in high critical temperature thin film superconductor structures.

Abstract: A high-temperature superconducting thin film of compound oxide selected from the group consisting of:Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Ho.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Lu.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x,Sm.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Nd.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Gd.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x,Eu.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Er.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Dy.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x,Tm.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, Yb.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, La.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x,(La, Sr).sub.2 CuO.sub.4-x,which is deposited on a substrate of MgO or SrTiO.sub.3, with the outer surface of the high-temperature superconducting thin film being covered with a protective crystalline film of SrTiO.sub.3.

Abstract: An elongate superconductor wiring element having, as seen in section, oxide superconductor material regions in each of which the c-axes of the oxide superconductor crystals are aligned with each other and are transverse to the longitudinal axis of the element. To reduce the dependence of critical current density on angular position of the element relative to a magnetic field, there are a plurality of said regions whose alignment directions of the c-axes are different as between different ones of said regions, so that the wiring element comprises a plurality of said regions having respectively different c-axis alignment directions.

Abstract: Metal-ceramic composite materials which combine advantageous properties of ceramic and metal and have the composition (Mg.sub.1-x Cu.sub.x)O+Ag.sub.y, where 0.03.ltoreq.x.ltoreq.0.25 and 0.001.ltoreq.y.ltoreq.0.5, can be produced in a one-stage process. In this process, sintering is carried out in air at a sintering temperature in the temperature range of 980.degree. C.-1100.degree. C. for a sintering time in the range of 1.5-2.5 hours. The rate of temperature rise from room temperature to the sintering temperature is in the range of 8-50 K/min. When 0.01.ltoreq.y.ltoreq.0.1, such composite materials are suitable as materials having high toughness for low-friction, self-lubricating sliding bearings, in particular of ceramic. When 0.1.ltoreq.y.ltoreq.0.2, they are suitable as electrical contact materials in fuel cells and for abrasion-resistant sliding contacts. When 0.15.ltoreq.y.ltoreq.0.5, the composite materials have a high conductivity.

Abstract: A superconductive device (e.g., magnet) having a superconductive lead assembly and cooled by a cryocooler coldhead having first and second stages. A first ceramic superconductive lead has a first end thermally connected to the first stage and a second end thermally connected to the second stage. A jacket of open cell material (e.g., polystyrene foam) is in surrounding compressive contact with the first ceramic superconductive lead, and a rigid, nonporous support tube surrounds the jacket. This protects the first ceramic superconductive lead against shock and vibration while in the device. The rigid support tube has a first end and a second end, with the second end thermally connected to the second stage.

Abstract: A method is provided for producing polycrystalline superconductor materials which utilizes a zdense and non-polluting 211 substrate which has been pre-sintered prior to melt processing with a 123 superconducting material. The resulting melt-processed material may be fabricated into a 123 superconductor having a single crystal size of up to 60 mm long which can carry very high current of up to about 1,500 A at 1 .mu.V/cm criterion.

Abstract: A substrate having a superconducting thin film of compound oxide thereon. An intermediate layer consists of at least one layer of copper-containing oxide is interposed between the substrate and the superconducting thin film.

Abstract: c-axis oriented high temperature superconductors are deposited onto new compositions of garnets using pulsed laser deposition (PLD) with conditions of 85 mTorr of oxygen partial pressure; a block temperature of 730.degree. C., a substrate surface temperature of 790.degree. C. and a laser fluence of 1 to 2 Joules/cm.sup.2 at the target, a laser repetition rate of 10 Hz and a target to substrate distance of 7 cm and in which the a and b lattice parameters of the new compositions of garnets exhibit a mismatch of less than 7 percent with the a and b lattice parameters of the HTSC.

Abstract: A system and method for mechanically forming a ceramic superconductor product. A system for making the ceramic superconductor includes a metallic channel portion having a cross section for receiving a ceramic superconductor powder, a roll to mechanically reduce the channel cross section and included superconductor powder and a cap portion welded to the channel portion using a localized high energy source. The assembled bar is then mechanically reduced to form a tape or wire end product.

Abstract: A superconducting thin film system (10) is provided for high frequency microwave applications where a single crystal high temperature superconducting layer (18) is integrated with a garnet substrate (12). A first perovskite compound buffer layer (14) is epitaxially grown on an upper surface of the garnet substrate layer (12) and defines a lattice constant less than the lattice constant of the garnet substrate layer (12). A second perovskite layer (16) is epitaxially grown on an upper surface of the first perovskite layer (14) and defines a lattice constant less than the lattice constant of the first perovskite layer. A high temperature superconducting layer (18) is epitaxially grown on an upper surface of the second perovskite layer (16) and is lattice matched to the second perovskite compound layer (16) for incorporation of passive components within the high temperature superconducting layer (18) having high frequency microwave applications.

Abstract: A superconducting oxide thin film device is composed of a LaAlO.sub.3 substrate and a YBCO thin film with a BaCeO.sub.3 buffer layer disposed between the two. The adhesion between the film and the substrate is increased by the presence of the buffer layer. The buffer layer also inhibits peeling of the film from the substrate and diffusion of Ba from the film into the substrate.

Abstract: A superconducting element is disclosed which comprises a lower superconducting layer, an upper superconducting layer, and an intermediate layer interposed between the lower and upper superconducting layers. The lower and upper superconducting layers are both form of a superconducting cuprate. The intermediate layer is formed of a layered cuprate containing in the crystal structure thereof multiple fluorite blocks represented by the formula:[B]AE.sub.2 (RE1.sub.1-y RE2.sub.y).sub.m+1 Cu.sub.2 O.sub.z(wherein [B] stands for a block layer, AE for an alkaline earth element, RE1 for at least one element selected from the group consisting of lanthanide elements and actinoid elements which form ions of valency of larger than 3, RE2 for at least one element selected from the group consisting of lanthanide elements which form ions of valency of 3 and yttrium, m for a number satisfying the expression m.gtoreq.2, y for a number satisfying the expression 0.ltoreq.y<1, and z for the oxygen content).

Abstract: A Josephson junction device is disclosed that includes a single crystalline substrate having a NaCl type crystal structure. The device includes a principal surface having two horizontal planes and a slope inclined at an angle of 5.degree. to 30.degree. between the two horizontal planes. An oxide superconductor thin film is formed on the principal surface of the substrate, which includes first and a second superconducting portions of a first single crystalline oxide superconductor and a second single crystalline oxide superconductor respectively positioned on the two horizontal planes of the substrate. A junction portion of a single crystalline oxide superconductor has a different crystal orientation from the first and the second superconducting portions, and is positioned on the slope of the substrate. Two grain boundaries between each of the first and the second superconducting portions and the junction portion constitute one weak link of the Josephson junction.

Abstract: A method of preparing a substrate with a view to depositing a thin layer of a superconductive material thereon, wherein an operation is performed of depositing on the substrate an intermediate material having the property of having a crystal lattice constant that is a function of the percentage of a doping element, the depositing operation being initiated with a concentration of the doping element such that the lattice constant of the intermediate material is equal to or as close as possible to the lattice constant of the substrate, the proportion of the doping element being continuously varied during the depositing operation to a proportion of the doping element such that the lattice constant of the intermediate material is equal to or as close as possible to the lattice constant of the superconductive material.

Abstract: A superconducting device comprises a substrate having a principal surface, a non-superconducting oxide layer having a similar crystal structure to that of an oxide superconductor formed on the principal surface, which can compensates the lattice mismatch between the substrate and the oxide superconductor, a superconducting source region and a superconducting drain region formed of c-axis oriented oxide superconductor thin films on the non-superconducting oxide layer, and an insulating region formed of a doped oxide superconductor on the non-superconducting oxide layer separating the superconducting source region and the superconducting drain region between them. On the insulating region an extremely thin superconducting channel formed of a c-axis oriented oxide superconductor thin film is arranged.