Abstract: A Josephson junction device includes a substrate, an oxide thin film formed on a portion of the principal surface of the substrate, which is constituted of a single crystal of which lattices shift at angle of 45.degree. to that of the principal surface of the substrate. One of the two portions of the oxide superconductor thin film is formed on the oxide thin film and the other portion of the superconductor thin film is formed on the principal surface of the substrate directly so that the lattices of the two portions of the oxide superconductor thin film are respectively linear up to those of the oxide thin film and the principal surface of the substrate and the grain boundary. The grain boundary which constitutes a weak link of the Josephson junction is formed just on the step portion formed of the oxide thin film.

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 forming a high-Tc microbridge superconductor device is disclosed, which comprises the steps of forming an inclined step on the surface of a substrate, the inclined step having an angle of inclination of from about 20 to about 80 degrees; depositing a layer of c-axis oriented superconductor material overlying the substrate such that there is a break in the layer of superconductor material at the inclined step; and depositing a layer of normal material overlying the layer of c-axis oriented superconductor material.

Abstract: A lattice matching device includes a substrate having thereon monocrystal regions having different lattice mismatches with respect to a LnBa.sub.2 Cu.sub.3 O.sub.x superconductor. A superconducting thin film is formed on the substrate, which film consists essentially of a superconductor of LnBa.sub.2 Cu.sub.3 O.sub.x wherein Ln represents yttrium or a lanthanide, and 6<x<7. The first and second superconducting thin film portions have different axes of orientation perpendicular to a main surface of the substrate, and arranged in contact with each other or at a distance which allows transmission of electron pairs from one to another.

Abstract: This invention relates to a process of forming multilayered thallium-containing superconducting composites, wherein a first thallium-containing superconducting layer, an intermediate thallium-containing oxide layer and a second thallium-containing superconducting layer are successively deposited on a substrate by a vapor phase process by controlling the heating temperature, pressure of oxidizing gas and thallium vapor pressure during post-deposition annealing of the superconducting films.

Abstract: For manufacturing a superconducting device having a tunnel junction formed of an extremely thin insulator layer sandwiched between a pair of oxide superconductor thin films, a first superconducting layer of oxide superconductor thin film is formed on a substrate, and a MgO thin film is deposited on the first superconducting layer at a substrate temperature of not higher than 200.degree. C. The MgO thin film is heat-treated so that crystallinity of the deposited MgO thin film is improved, and thereafter, a second superconducting layer of oxide superconductor thin film is formed on the MgO thin film.

Abstract: An oxide superconductor thin film is formed on a substrate by emitting molecular beams of constituent elements of the oxide superconductor to the substrate under high vacuum, wherein at first a molecular beam of one of the constituent elements of the oxide superconductor, of which an oxide thin film can be deposited so as to have a smooth surface, is emitted so as to form the oxide thin film of one or two unit cells. And then, all the molecular beams of constituent elements of the oxide superconductor are emitted to the oxide thin film so as to form the oxide superconductor thin film.

Abstract: A superconductor element includes a first layer of an oxide superconductor, a second layer of an insulator, semiconductor, or metal, and an interlayer interposed between the first and second layers and formed of AgO.sub.x (where in 0<.times.< 1/2) .

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 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 manufacturing method of a superconducting pattern is described. A superconducting ceramic film is deposited on a non-conductive surface and partly spoiled in order to form a barrier film by which two superconducting regions is separated. The spoiling is performed by adding a spoiling element into the ceramic film by ion implantation.

Abstract: The invention relates to a method of manufacturing a superconducting device, which comprises the steps of forming on a principal surface of a substrate a non-superconducting oxide layer having a similar crystal structure to that of a c-axis oriented oxide superconductor thin film and a flat-top projection at its center portion, forming a c-axis oriented oxide superconductor thin film having an extremely thin thickness on the non-superconducting oxide layer so as to form a superconducting channel on the projecting portion of the non-superconducting oxide layer, forming an insulating layer on the c-axis oriented oxide superconductor thin film so as to form a gate insulating layer on the superconducting channel, and forming an a-axis oriented oxide superconductor thin film so as to form a superconducting source region and a superconducting drain region of which upper surfaces have the same level as that of the superconducting channel.

Abstract: A superconductor device is provided including a base, a base electrode formed on the base which is made of a Bi-system oxide superconductive material containing an alkaline earth metal, a barrier layer formed on the base electrode which is made of Bi--Sr--Cu--O, a counter electrode formed on the barrier layer which is made of a Bi-system oxide superconductive material containing an alkaline earth metal, a contact electrode formed so as contact with the counter electrode, and a separation layer for separating said contact electrode from said base electrode.

Abstract: A shielding sleeve (19) for SQUID-magnetometers which serves to shield from electromagnetic interference fields, consists of an electrically conductive shielding material so as to obtain adequate RF shielding in conjunction with a low noise contribution, completely envelops a non-shielding cryostat (10), has a predetermined sheet resistance and consists of at least one layer of the shielding material in order to avoid an increase of the magnetometer overall noise.

Abstract: An anisotropic superconductor junction device consisting of a lower superconducting layer and an upper superconducting layer separated by a barrier layer, in which the upper and lower superconducting layers and the barrier layer each have a (103) crystal orientation in which the c axis is arranged in the same direction at an angle of 45 degrees relative to the plane of the junction.

Abstract: A superconducting device has a structure of superconductor--normal--conductor (semiconductor)--superconductor. The superconducting regions and the normal-conductor region can be made of the same elements but having different relative proportions of the elements. The device can be fabricated by introducing at least one element into an unmasked region of the superconductor to form a normal conductor region or into unmasked regions of the normal conductor to form superconductor regions.

Abstract: A method of manufacturing a superconducting device involves forming a thin film on the surface of a substrate, forming a superconducting gate electrode on a portion of the thin film, etching the portions of the thin film using the gate electrode as a mask thereby providing a superconducting channel under the gate, forming a step portion on the superconducting channel and under the gate, converting the oxide portion of the step portion into a gate insulation portion by heating the substrate in a vacuum, forming a second oxide superconducting film on the exposed surface of the channel so that superconducting source and drain electrodes are formed on each side of the gate such that the drain and source have a thickness greater than that of the channel and are electrically isolated from the gate electrode.

Abstract: The disclosed superconductive optoelectronic device with the basic substance Bi.sub.2 O.sub.3 or Bi.sub.2 O.sub.3 ;M.sup.2+ (M=Ca,Sr,Cu) of superconductive-conjugate photoconductivity has a substrate, a photoconductive gate region formed on the substrate, and a source region and a drain region formed on the substrate at opposite sides of the gate region so as to face toward each other across the gate region. The source region and the drain region are made of a Bi-based superconductive material. The gate region is made of such the basic material Bi.sub.2 O.sub.3 or Bi.sub.2 O.sub.3 ;M.sup.2+ (M=Ca,Sr,Cu) of superconductive-conjugate photoconductivity, which reveals photoconductivity at a temperature below the transition temperature of the above relevant Bi-based superconductive material. Also disclosed are superconductive optoelectronic devices formed of an organized integration of the above superconductive optoelectronic devices to develop effectively a new field of "Superconductive Optoelectronics".

Abstract: A method for producing multilayer structures comprised of materials with incompatible processing parameters is disclosed. A bonding layer of arbitrary dielectric constant is applied to each of two substructures. Each substructure is composed of a substrate and at least one epitaxial crystalline layer. Examples of particular bonding materials used are polyimide, fluorocarbon polymers, other organic materials, and glass. The bonding material may be applied like photoresist, or sputtered, or applied in any appropriate manner consistent with the processing constraints of the crystalline materials. Structures formable in this way include superconductor-amorphous dielectric-superconductor and ferroelectric-insulator-semiconductor trilayers, as well as microwave resonators and multichip modules.

Abstract: An outer surface of a superconducting thin film of compound oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-.delta. deposited on a substrate such as MgO and SrTiO.sub.3 is protected with a protective layer which is composed of amorphous inorganic material such as inorganic glass, amorphous oxide.

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 method for forming a patterned oxide superconductor thin film on a substrate comprises steps of forming a metal or semi-metal layer on a portion of the substrate, on which the oxide superconductor thin film will be formed, forming a layer of a material including silicon on a portion of the substrate, on which an insulating layer will be formed, removing the metal or semi-metal layer and depositing an oxide superconductor thin film over the substrate.

Abstract: A method for depositing a thin film of a material on an oxide thin film having a perovskite type crystal structure formed on a substrate comprising steps of depositing a seed layer of a single crystal of the material having an extremely thin thickness at a relatively high substrate temperature on the oxide thin film having a perovskite type crystal structure and depositing a thin film of the material on the seed layer at a lower substrate temperature.

Abstract: A SQUID comprises a substrate, a washer of an oxide superconductor thin film formed on a principal surface of the substrate, a hole shaped a similar figure to the washer at the center of the washer, a slit formed between one side of the washer and the hole, and a Josephson junction which connects portions of the washer at the both sides of the slit across the slit. In the SQUID, the ratio of similarity of the washer to the hole ranges 100 to 2500.

Abstract: A thin-film superconductor includes a substrate, a ferroelectric film, and a superconducting oxide film. The ferroelectric film extends on the substrate. The ferroelectric film is made of a crystal contains Bi and O. The superconducting oxide film extends on the ferroelectric film, and containing Bi, Cu, and an alkaline-earth metal element. The superconducting oxide film may contain at least two different alkaline-earth metal elements.

Abstract: A weak link is patterned from a high-temperature superconducting film using standard lithographic techniques. Once the area in which the weak link is to be located is defined, the remainder of the film is covered with an oxygen-impermeable material. The oxygen is then removed in the weak link area by placing the sample in a vacuum furnace at a sufficient temperature to drive out the oxygen. Once the oxygen is removed, the weak link becomes non-superconducting. A high power solid state laser is placed in front of the weak link, and superconductivity is restored in the weak link area, in situ. The process is performed in a liquid nitrogen environment.

Abstract: c-axis oriented YBa.sub.2 Cu.sub.3 O.sub.7 layers are grown with intervening SrTiO.sub.3 layers bridged over steps at which there is a transformation to a-axis crystal-oriented growth. The multilayer superconductor has YBa.sub.2 Cu.sub.3 O.sub.7 layers which are not thicker than 500 nm while the intervening layers of SrTiO.sub.3 have thicknesses of 20 to 30 nm.

Abstract: An oxide-superconducting device comprises first and second electrodes of oxide-superconductor which are connected through a tunnel barrier layer. The oxide-superconductor is formed on a substrate having a recess, and it includes grain boundaries along the recess. The tunnel barrier layer is formed along the grain boundaries, and it is made of any material of an element F, Cl, Br, I, C, O, S, P or N, a mixture consisting of such elements, and a compound containing such an element, the material being introduced into the grain boundaries and/or lattice interstices near the grain boundaries.

Abstract: A thin film device comprising a substrate and an oxide superconductor film formed thereon, wherein said oxide superconductor film comprises atomic monolayers each composed of at least one kind of element of the oxide superconductor, which are deposited substantially in a vertical direction to the substrate so that the pereodicy of the lattice structure of the oxide superconductor is substantially maintained, and at an intermediate portion of the oxide superconductor film, at least a part of the atoms of the oxide superconductor is substituted by other element in the lattice structure of the oxide superconductor to form a non-superconductor interlayer, and the pereodicy of the lattice structure of the oxide superconductor film is substantially maintained across the interface between the oxide superconductor and said non-superconductor interlayer.

Abstract: A Josephson junction device comprising a single crystalline substrate including a principal surface having two horizontal planes and a smooth slope between the two horizontal planes, and an oxide superconductor thin film formed on the principal surface of the substrate. The oxide superconductor thin film includes a first and a second superconducting portions of a single crystalline oxide superconductor respectively positioned on the two horizontal planes of the substrate, a junction portion of a single crystalline oxide superconductor having a different crystal orientation from the two superconducting portions positioned on the slope of the substrate and two grain boundaries between each of the two superconducting portions and the junction portion. The grain boundaries constitutes one weak link of the Josephson junction.

Abstract: The invention relates to a structured superconductive track and a process for making it from epitaxial high temperature superconductor (HTSC) layers using lift off technique, in which a HTSC track deposited on an elevated substrate region is surrounded by an insulating layer of doped HTSC lying on a lower substrate region, and the substrate region with the superconductive track formed thereon is elevated such that the superconductive track is isolated from the insulating layer.

Abstract: A superconducting device has a superconducting channel formed of an oxide superconductor on the principal surface of a substrate. A source electrode and a drain electrode likewise formed of oxide superconductor, are electrically connected by the channel to provide for superconducting current flow. A superconducting gate electrode is isolated by a side insulating region which completely covers each of opposite side surfaces of the gate electrode. The relative thicknesses of both the source and drain electrodes are much greater than that of the channel thickness. The superconducting channel and the gate insulator are both formed by one oxide thin film, and in a preferred embodiment, the gate electrode likewise is provided by the same film which forms the gate insulator and channel.

Abstract: A novel method for fabricating nanometer geometry electronic devices is described. Such Josephson junctions can be accurately and reproducibly manufactured employing photolithographic and direct write electron beam lithography techniques in combination with aqueous etchants. In particular, a method is described for manufacturing planar Josephson junctions from high temperature superconducting material.

Abstract: A hysteretic high-T.sub.c trilayer Josephson junction, and a method of forming the same are disclosed. The junction includes lower and upper high T.sub.c superconducting cuprate films separated by a barrier layer, where the thin films each include a molecular junction layer adjacent the barrier layer which is characterized by a high-T.sub.c cuprate stoichiometry and crystal structure, and a flat two-dimensional surface, as evidenced by its electron diffraction pattern using reflected high-energy electron diffraction. The junction and barrier layers in the junction are formed by atomic layer-by-layer deposition.

Abstract: The disclosure relates to a Josephson junction formed by a non-superconducting barrier between two superconducting films of the (R) BaCuO (R=rare earth) group. In order to take advantage of the greater coherence length of superconductors along the CuO planes, i.e. perpendicularly to the long axis "c" of the crystal unit cell, the superconducting film is oriented so that the axis "c" is parallel to the plane of the junction. The device can be applied to Josephson junctions and to SQUIDs.

Abstract: A thin film superconductor assembly is disclosed along with a method of fabricating same. The assembly comprises a self-supporting substrate defining at least a portion of a containment for a flow of cryogenic fluid, a dielectric layer adherent to a surface of the substrate, a thin film superconductor adherent to the dielectric layer and a moisture and oxygen impervious electrically insulating coating covering the thin film superconductor. A method of forming such thin film superconductor assembly, wherein the dielectric layer consists essentially of aluminum nitride, comprises growing the aluminum nitride dielectric layer integrally on the surface of the substrate.

Abstract: A Josephson break junction device suitable for highly sensitive electronic detecting systems. A superconductor film such as YBa.sub.2 Al.sub.3 O.sub.7 is deposited on a substrate such as a single-crystal MgO. The film is fractured across a narrow strip by at least one indentation in the substrate juxtaposed from the strip to form a break junction. A transducer is affixed to the substrate for applying a bending movement to the substrate to regulate the distance across the gap formed at the fracture to produce a Josephson turned junction effect. Alternatively, or in addition to the transducer, a bridge of a nobel metal is applied across the gap to produce a weak-link junction.

Abstract: An insulating composition consisting of Bi, Sr, RE, Cu, O or of Tl, Ba, RE, Cu, O (wherein; RE is an element selected from a group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y) aligns properly with a crystal face of an oxide superconductor because its crystal structure is the same as or similar to that of the oxide superconductor. An insulating composition in which a part of Bi is replaced by Pb is further near the oxide superconductor its construction, and the modulation structure in this insulating composition is mitigated or disappears.

Abstract: An atmospheric process for the production of a coating of film upon a nickel-containing substrate. In the first step of this process, an aerosol mist containing reactants necessary to form the coating is provided. Thereafter, the mist is subjected to radio-frequency radiation while in the plasma region. Thereafter, the vaporized mixture is then deposited onto a nickel substrate. In subsequent steps, one or more other layers of vaporized material may be deposited onto the coated substrate.

Abstract: Disclosed is an article that comprises a superconductor-insulator (s-i) layer structure. The superconductor material has nominal composition Ba.sub.1-x M.sub.x BiO.sub.3-y (M is K, Rb, or K and Rb, 0.35<x.ltorsim.0.5, 0<y.ltorsim.0.25). In some preferred embodiments the insulator is a Ba- and Bi containing oxide, exemplarily BaBi.sub.2 O.sub.4, Ba.sub.1-x M.sub.x BiO.sub.3 (0.ltoreq.x<0.35), or Ba.sub.1-x Bi.sub.1+x O.sub.3 (0.ltoreq.x.ltorsim.0.5). In other embodiments the insulator is an insulating oxide with the NaCl structure (e.g., Mg.sub.1-x Ca.sub.x O), an insulating perovskite (e.g., BaZrO.sub.3 ), an insulator with the K.sub.2 NiF.sub.4 structure (e.g., Ba.sub.2 PbO.sub.4), an insulating fluoride with the BaF.sub.2 structure (e.g., Ba.sub.1-x Sr.sub.x F.sub.2), or an insulating fluoride with the NaCl structure (e.g., LiF). Disclosed are also advantageous methods of making an article according to the invention.

Abstract: A process for formulating non-hysteretic and hysteretic Josephson junctions using HTS materials which results in junctions having the ability to operate at high temperatures while maintaining high uniformity and quality. The non-hysteretic Josephson junction is formed by step-etching a LaAlO.sub.3 crystal substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed the next step to form the hysteretic Josephson junction is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaA1O.sub.3, followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry.

Abstract: Novel articles are provided of thin super-conductive thallium-based copper oxide layers on inorganic, usually crystalline substrates. Novel methods are provided for ease of producing such articles, particularly involving sol-gel techniques and laser ablation. The articles have a highly oriented superconductive thallium-based copper oxide film, particularly epitaxial, with high superconductive transition temperatures and desirable electrical properties. The subject articles find use in a wide variety of electronic applications, particularly in microwave and millimeter wave devices.

Abstract: A method, and the resulting structure, of growing a superconducting perovskite thin film of, for example YBa.sub.2 Cu.sub.3 O.sub.7-x. A buffer layer of, for example, the perovskite PrBa.sub.2 Cu.sub.3 O.sub.7-y, is grown on a crystalline (001) substrate under conditions which favor growth of a,b-axis oriented material. Then the YBa.sub.2 Cu.sub.3 O.sub.7-x layer is deposited on the buffer layer under changed growth conditions that favor growth of c-axis oriented material on the substrate, for example, the substrate temperature is raised by 110.degree. C. However, the buffer layer acts as a template that forces the growth of a,b-axis YBa.sub.2 Cu.sub.3 O.sub.7-x, which nonetheless shows a superconducting transition temperature near that of c-axis oriented films.

Abstract: A portion of a sufficiently thick insulating layer formed on a substrate is removed so that a recessed device region is formed and surrounded by masking wall portions left at both ends of the recessed device region. A first oxide superconducting thin film is deposited at angle of 30.degree. to the substrate so as to ensure that a c-axis oriented oxide superconducting thin film grows in such a way that a portion of the recessed device region is masked by one of the masking wall portions so that no thin film grows over the masked portion of the recessed device region. Then, another oxide superconducting thin film is deposited at angle of -30.degree.

Abstract: A method for applying a metal film barrier layer between a substrate and a superconductor coating or over a superconductivity coating using chemical vapor deposition in which low vapor pressure reactants are used, is disclosed, which comprises the steps of providing a substrate and a quantity of metal-bearing reagent and one or more reagents, placing the substrate within the furnace, introducing the metal-bearing reagent by a powder feeder means and then the reagents at different times into and reacting them in the furnace, resulting in the deposition first of a coating of metal onto the substrate and then of a coating consisting essentially of the superconducting reactant components onto the metal film; said reagents generally chosen to yield the group of oxide superconductors.

Abstract: An article comprises an oriented thick film superconducting coating on a polycrystalline substrate. The coating includes at least two highly oriented platelet components ofBi.sub.a Sr.sub.b Ca.sub.c Cu.sub.d O.sub.x (BSCCO)wherein, in one component, a is 2, b is 2, c is 1, d is 2, and x is 8 and, in another component, a is 2, b is 2, c is 0, d is 1, and x is .apprxeq.6, oriented such that said BSCCO platelets are essentially parallel to said substrate. Suitable polycrystalline substrates are MgO and alumina and mullite.

Abstract: A superconducting tunnel element, having a plurality of super conductors separated by barriers, the superconductors each comprising two physically separate but electrically connected superconducting layers and one insulated control layer. As a result, summation of the detection capacity or of the transmitting intensity becomes possible. Also, the simultaneous detection or transmission is permitted on arbitrary different frequencies or a summation of the signal intensity is possible in the case of SQUID-systems.

Abstract: Josephson contacts are fabricated in ceramic compounds from classes of high temperature superconductors. The succession of layers in the single-crystal determines the properties of the Josephson contacts. The supercurrent flows in the direction of the crystallographic c-axis. In a category of substances of high temperature superconductors the Josephson contacts are located in the space between each of two copper oxide planes. In a different class of high temperature superconductors the Josephson contacts are located between each of two single copper oxide planes. The electrical properties such as critical supercurrent density, capacitance and shunt resistance or the Josephson contacts are adjusted by controlled addition or controlled withdrawal of oxygen. Using stacks of such intrinsic Josephson contacts within a single-crystal, current-controllable high frequency generators, Josephson voltage normals and SQUIDS can be realized.

Abstract: Rare-earth alkaline metal titanates are used as buffer layers substrates, and oxygen diffusion barriers for the growth of high critical temperature superconductors, ferroelectrics, pyroelectrics and piezoelectrics.

Abstract: A superconducting device has a structure of superconductor - normal-conductor (semiconductor) - superconductor. The superconductors constituting the superconducting device are made of a superconducting oxide material of K.sub.2 NiF.sub.4 type crystal-line structure or perovskite type crystalline structure which contains at least one element selected from the group consisting of Ba, Sr, Ca, Mg and Ra; at least one element selected from the group consisting of La, Y, Ce, Sc, Sm, Eu, Er, Gd, Ho, Yb, Nd, Pr, Lu and Tb; Cu; and O.