Abstract: Active superconductive devices are formed having a variable conductive element in electromagnetic contact with a superconductor. In one embodiment, a variable ohmic conductive device, such as a photoconductor, is placed adjacent a superconductor. By varying the optical radiation on the photoconductor, the electromagnetic environment adjacent the superconductor is changed, resulting in changed electrical properties. The superconductor may be patterned as a reject filter, with a photoconductor forming a microwave switch. Alternatively, a delay line plus variable ohmic element forms a phase shifter.

Abstract: A planar type superconductive thin film transistor using oxide superconductive materials and utilizing a long distance proximity effect is obtained with a good reproducibility.In order to obtain the planar type superconductive transistor utilizing the long distance proximity effect, an interlayer separating film that plays a similar role with resists is used together with conventional resists in high temperature annealing process.

Abstract: The invention is directed to a superconducting microwave resonator, to holding devices for those resonators, and to their methods of manufacture. The superconducting microwave resonator employs at least two superconducting films on substrates positioned on a dielectric. The holding devices include a variety of configurations, such as, a spring loaded device. The superconducting microwave resonators have Q values of as high as microwave resonators formed of Nb, but operate at much higher temperature.

Abstract: An article of manufacture having an epitaxial (111) magnesium oxide (MgO) layer, suitable for use as a buffer layer, on a (111) surface of a tetrahedral semiconductor substrate, and method for its manufacture is described. The article may further include an epitaxial oxide overlayer on the (111) MgO layer. The overlayer may be a conducting, superconducting, and/or ferroelectric oxide layer. The method of producing the epitaxial (111) magnesium oxide (MgO) layer on the (111) surface of a tetrahedral semiconductor substrate proceeds at low temperature. The method may further include steps for forming the epitaxial oxide layer on the (111) MgO layer. The methods include the steps of preparing the (111) surface of a tetrahedral semiconductor substrate for deposition and the low temperature depositing of an MgO layer on the prepared surface. Further steps may include the depositing of the oxide layer over the MgO layer.

Abstract: A Josephson break junction device suitable for highly sensitive electronic detecting systems. A superconductor film such as YBa.sub.2 Cu.sub.3 O.sub.7 is deposited on a substrate such as a simple-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 novel metal is applied across the gap to produce a weak-link junction.

Abstract: A superconducting transistor is provided with a base layer made of a normal conductor metal, an emitter layer made of a superconductor for injecting hot electrons to the base layer, a collector layer made of a superconductor for trapping electrons from the base layer, a first tunnel barrier layer made of an insulator and provided between the base layer and the emitter layer, and a second tunnel barrier layer made of an insulator and provided between the base layer and the collector layer.

Abstract: According to the present invention, when a superconductive thin film is formed on a substrate of a single crystal, a compound having a composition of SrNdGaO.sub.4 and a K.sub.2 NiF.sub.4 type crystal structure is used as a material employable for the substrate. Alternatively, a single crystal composed of an oxide in which Ca, La and Cr are added to the foregoing compound is used as a material employable for the substrate. Then, a superconductive thin film composed of an oxide is formed on the substrate by employing an epitaxial growing method. Thus, the present invention makes it possible to provide a superconductive material having an excellent property of lattice alignment, a stable and high critical superconductivity temperature and a stable critical superconductivity electric current.

Abstract: A process for preparing a thin film of oxide superconductor on a single crystal substrate of semiconductor by RF sputtering. At first, an under-layer of an oxide having a thickness of 50 to 200 .ANG. is deposited on the single crystal substrate of semiconductor at a substrate temperature of lower than 500.degree. C., and secondly an upper-layer of superconducting oxide material is deposited on said under-layer at a substrate temperature of higher than 600.degree. C.

Abstract: A method for manufacturing a high Tc superconducting circuit elements is disclosed, which comprises the steps of preparing a single crystal conductive substrate of Sr.sub.2 RuO.sub.4 by a floating zone melting process; epitaxially growing on the (001)-surface of the Sr.sub.2 RuO.sub.4 substrate a high Tc copper oxide-based superconducting film with a thickness of 1 to 1000 nm; depositing metal pads onto said superconducting film to form electrical contacts; and applying a metal pad to the surface of the substrate to form an electrical contact.

Abstract: A process for etching with a scanning tunneling microscope on both a single crystal and a thin film of high temperature superconductor is disclosed.

Abstract: A beam (e.g. a focused laser beam) is utilized to irradiate the entire lateral width of a limited-extent portion of an elongated superconducting thin-film lead. The irradiated portion is converted to be non-superconducting and photoconductive. The converted portion constitutes a photodetector integrated with associated superconducting leads.

Abstract: Disclosed herein is a ceramic superconductor comprising a ceramic superconductive member, and a high-conductivity metal layer covering the ceramic superconductive member. At least one portion of the metal layer having low electrical conductivity or low thermal conductivity. Also disclosed is a method of manufacturing a ceramic superconductor, comprising the steps of filling a ceramic superconductor or a precursor thereof in a high-conductivity metal pipe, thereby forming a composite member, rolling the composite member into a ceramic superconductor element of a desired shape, which comprises a ceramic superconductive member and a high-conductivity metal layer covering the ceramic superconductive member, performing a predetermined heat treatment on the ceramic superconductor element, and alloying a predetermined portion of the high-conductivity metal layer, thereby rendering the portion less conductive either electrically or thermally.

Abstract: An epitaxial structure comprising a silicon containing substrate and a high T.sub.c copper-oxide-based superconducting layer, which may include an intermediate layer between the silicon substrate and the superconductor layer. Epitaxial deposition is accomplished by depositing a superconductor on a (001) surface of silicon in a manner in which the unit cell of the superconductor layer has two out of three of its crystallographic axes rotated 45 degrees with respect to the corresponding axes of the silicon unit cell, the remaining axis of the superconductor unit cell being normal to the Si (001) surface.

Abstract: A microwave cavity including a pair of opposing clamshell halves, such halves comprised of a metal selected from the group consisting of silver, copper, or a silver-based alloy, wherein the cavity is further characterized as exhibiting a dominant TE.sub.011 mode is provided together with an embodiment wherein the interior concave surfaces of the clamshell halves are coated with a superconductive material. In the case of copper clamshell halves, the microwave cavity has a Q-value of about 1.2.times.10.sup.5 as measured at a temperature of 10K and a frequency of 10 GHz.

Abstract: Improvement in a process for fabricating a superconducting junction by depositing successively a first oxide superconductor thin layer, a non-superconducting intermediate thin film layer and a second oxide superconductor thin film layer on a substrate in this order.In the invention, the non-superconducting intermediate thin film layer is composed of MgO and the substrate is preheated at 600.degree.-650.degree. C. for at least 5 minutes in the presence of O.sub.2, and is heated at a temperature between 200.degree. and 400.degree. C. during the non-superconducting intermediate thin film layer is deposited.

Abstract: Thin protective polyimide layers are produced on ceramic or high temperature superconductors by applying polyimide solutions, polyamic acids or starting substances therefor to the superconductor surface and imidating or drying in an oxygen atmosphere.

Abstract: This invention relates to new superconducting material having a composition represented by the general formula:A.sub.u B.sub.v C.sub.w D.sub.x E.sub.

Abstract: A superconducting circuit board is provided comprising a sintered alumina board containing more than 99% by weight of alumina and an interconnection pattern of an superconducting ceramics formed on the alumina board. Adhesion of the interconnection pattern to the alumina board is improved by an addition of Ti or Si coupling agent to a paste for forming the interconnection pattern. The use of copper powder in place of copper oxide powder as an ingredient forming a superconducting ceramics in the paste is advantageous for printing and obtaining a uniform superconducting ceramic pattern.

Abstract: A superconducting optically reconfigurable device (SORD) wherein predetermined and optically achieved patterns of superconducting material generate Meissner effect magnetic flux to achieve control of physical characteristics in local areas of an adjacent film of electromagnetic energy controlling material. The superconducting material magnetic flux is remembered by way of a cycle wherein selected portions of the material are elevated from the superconducting temperature range through the critical temperature T.sub.c into the non-superconducting state while in the presence of a writing magnetic field and then cooled through the critical temperature T.sub.c to permanently retain the writing magnetic flux in the area of temporary optical warming. The pattern of magnetic flux thusly achieved is coupled to one of several possible electromagnetic energy influencing or controlling materials which also have magnetic flux susceptibility.

Abstract: A superconducting electronic circuit device, useful when impedance matching is desired, especially suited to microwave frequencies, consisting of a thin dielectric layer with superconducting layers on both sides. A superconductor such as Yttrium Barium Copper Oxide (YBCO) is formed on a first substrate such as lanthanum aluminate. A protective layer like gold is deposited on the YBCO and a second carrier substrate is bonded to the protected YBCO. The first substrate is then thinned into a thin dielectric film and a second layer of superconductor is epitaxially grown thereon to create the desired circuits.

Abstract: A method is disclosed for fabricating grain boundary junction devices, which comprises preparing a crystalline substrate containing at least one grain boundary therein, epitaxially depositing a high Tc superconducting layer on the substrate, patterning the superconducting layer to leave at least two superconducting regions on either side of the grain boundary and making electrical contacts to the superconducting regions so that bias currents can be produced across the grain boundary.

Abstract: This field-effect transistor comprises a conductive substrate (2) serving as the gate electrode, an insulating barrier layer (3), and a superconducting channel layer (1) on top of the barrier layer (3). The superconductor layer (1) carries a pair of mutually spaced electrodes (4, 5) forming source and drain, respectively. The substrate is provided with an appropriate gate contact (6).The substrate (2) consists of a material belonging to the same crystallographic family as the barrier layer (3). In a preferred embodiment, the substrate (2) is niobium-doped strontium titanate, the barrier layer (3) is undoped strontium titanate, and the superconductor (1) is a thin film of a material having a lattice constant at least approximately similar to the one of the materials of the substrate (2) and barrier (3) layers. A preferred material of this type is YBa.sub.2 Cu.sub.3 O.sub.7-.delta., where 0 .cent..delta..ltoreq.0.5.

Abstract: An alloy having a low reactivity towards certain high temperature superconducting materials at temperatures up to about 10.degree. C. lower than the melting point of the alloy. The alloy is a ternary silver-based alloy consisting, by weight, of 0.5-9% palladium, 20-40% gold, balance silver. Using the alloy and a superconducting material of the type R-Ba-Cu-O, where R is yttrium or a rare earth element, composite conductors can be formed at temperatures equal or higher than the temperature of peritectic decomposition of the superconductor. The alloy may also be used as a buffer layer or cladding material on substrates having unacceptably high reactivity towards the superconducting material.

Abstract: An oxide superconductor having a high critical temperature is provided with a passivation coating comprising a first layer of a Group II oxide, such as magnesium oxide, and a second layer of a polymer, such as polyimide. The Group II oxide is formed under conditions to be substantially amorphous. After depositing the Group II, layer, the encapsulated superconductor is heated to an elevated temperature for a period of time in an oxidizing atmosphere. This restores the high critical temperature to its original value. The polymer is then coated on top of the Group II oxide and cured. The passivation coating is resistant to strong acids, strong bases, and water, is robust, hard, and resilient against scratching.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing barium. The process utilizes a temperature regime which overcomes problems associated with degradation of barium-containing multicomponent oxides caused by carbon dioxide.

Abstract: A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template layThis invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

Abstract: These superconducting circuit elements, namely SNS heterostructures, such as, e.g. Josephson junctions and field-effect transistors, have a sandwich structure consisting of at least one layer of high-T.sub.c superconductor material arranged adjacent to a metallic substrate, possibly with an insulating layer in between, the substrate, the superconductor and--if present--the insulator all consisting of materials having at least approximately matching molecular structures and lattice constants. Electrical contacts, such as source, drain and gate electrodes are attached to the superconductor layer and to the substrate, respectively. The electrically conductive substrate consists of a metallic oxide such as strontium ruthenate Sr.sub.2 RuO.sub.4, whereas the superconductor layer is of the copper oxide type and may be YBa.sub.2 Cu.sub.3 O.sub.7-.delta., for example. The insulator layer (10) may consist of SrTiO.sub.3.

Abstract: A detector useful for detecting infrared (IR) radiation is described which is formed of an epitaxial film of superconductive material having a high transition temperature Tc. Specifically, an oxide of yttrium barium and copper is preferred for the high Tc material. The sensor is formed on a single crystalline silicon body suspended by a silicon nitride membrane over a gap formed in a silicon base body and thermally isolated thereby.

Abstract: A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing strontium, calcium or magnesium. The process utilizes a temperature regime which overcomes problems associated with degradation of strontium-, calcium- and magnesium-containing multicomponent oxides caused by carbon dioxide.

Abstract: A superconducting network which, through the use of optical illumination, can form a selectable array of superconducting microstrip transmission lines or other electrical elements. The invention uses optical illumination to produce quasiparticles which cause selected physical parts of the network to be electrically nonconductive and thereby define the nonilluminated conductor's shape, physical size, and electrical characteristics. Network reconfigurability to produce several different devices and functions from a single high or low temperature superconductive chip is a disclosed utilization of the invention. The employed optical illumination produces phase change within the superconducting material to provide specific chip architectures. Reconfiguring of the device characteristics is achieved by changing the optical input intensity, spatial orientation, wavelength or combinations of these factors. A plurality of delay line configurations are disclosed as examples.

Abstract: A high efficiency integrating sphere that can be used in a large variety of scientific instruments. The sphere having an efficiency gain obtained by using a superconducting material, acting as a perfect reflector, on the inside hollow surface of the sphere. The sphere is operated with a delay between the incident and sensed light, heretofore not possible, and yielding substantial improvement in the signal-to noise ratio of the integrating sphere.

Abstract: A microelectronic component comprising a crossover is provided comprising a substrate, a first high T.sub.c superconductor thin film, a second insulating thin film comprising SrTiO.sub.3 ; and a third high T.sub.c superconducting film which has strips which crossover one or more areas of the first superconductor film. An insitu method for depositing all three films on a substrate is provided which does not require annealing steps. The photolithographic process is used to separately pattern the high T.sub.c superconductor thin films.

Abstract: A high temperature superconducting wire or yarn has a first layer thereon yttria, a third layer of barium cuprate, and a second layer of a superconducting YBa.sub.2 Cu.sub.3 O.sub.7-x formed at the interface between the first and third layers. The wire can be yttrium and the yarn can be alumina.

Abstract: An article of manufacture including a substrate, a patterned interlayer of a material selected from the group consisting of magnesium oxide, barium-titanium oxide or barium-zirconium oxide, the patterned interlayer material overcoated with a secondary interlayer material of yttria-stabilized zirconia or magnesium-aluminum oxide, upon the surface of the substrate whereby an intermediate article with an exposed surface of both the overcoated patterned interlayer and the substrate is formed, a coating of a buffer layer selected from the group consisting of cerium oxide, yttrium oxide, curium oxide, dysprosium oxide, erbium oxide, europium oxide, iron oxide, gadolinium oxide, holmium oxide, indium oxide, lanthanum oxide, manganese oxide, lutetium oxide, neodymium oxide, praseodymium oxide, plutonium oxide, samarium oxide, terbium oxide, thallium oxide, thulium oxide, yttrium oxide and ytterbium oxide over the entire exposed surface of the intermediate article, and, a ceramic superco nFIELD OF THE INVENTIONThe pre

Abstract: Improvement in a superconducting thin film of compound oxide represented by the formula: LnBa.sub.2 Cu.sub.3 O.sub.7- .delta. (Ln is lanthanide) or (La.sub.1-x .alpha..sub.x).sub.2 CuO.sub.4 (.alpha. is Ba or Sr) deposited on a substrate or core made of MgO, SrTiO.sub.3 or ZrO.sub.2 by physical vapor deposition technique, the surface roughness R.sub.max (datum length=1,000 .mu.m) of the superconducting thin film being less than 0.2 .mu.m.

Abstract: Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

Abstract: In a method of forming an oxide superconductor/semiconductor junction between an oxide superconductor and a semiconductor containing bismuth or thallium, an atomic layer of silver of no more than 3 atoms thickness is formed by vapor deposition of silver on the surface of the semiconductor, an atomic layer of bismuth or thallium of no more than 3 atoms thickness is formed by vapor deposition of bismuth or thallium on the silver layer, the double atomic layer consisting of silver and bismuth or of silver and thallium are heated to form a layer wherein the atoms of silver and bismuth or silver and thallium are arranged regularly on the surface of the semiconductor, and the oxide superconductor is formed to a specified thickness on the regularly arranged layer.

Abstract: A laminated film comprising at least two thin films of single crystal LnBa.sub.2 Cu.sub.3 O.sub.7-x wherein Ln is Y or one of lanthanoids except Pr and Tb having the (001) plane in the direction parallel with the film surface and at least one continuous thin film of Y.sub.2 O.sub.3 which has a thickness of not larger than 100 .ANG. and the (001) plane in the direction parallel with the film surface and is interposed between a pair of said thin films of single crystal LnBa.sub.2 Cu.sub.3 O.sub.7-x, wherein the thin films of single crystal LnBa.sub.2 Cu.sub.3 O.sub.7-x has good superconductive properties.

Abstract: A method of forming a superconductor pattern in which at lest a pair of electrodes is formed on a substrate in spaced, facing relationship nd an oxide superconductor thin film having a unit lattice which assumes a laminar structure then is formed on the substrate, extending between and contacting the electrodes. The superconductor pattern obtained by this method suffers less degradation of the superconductor thin film, in comparison with that of patterns formed by the prior art methods, and the decrease of the critical current density as a function of increasing temperature is extremely small.

Abstract: A superconducting conductor assembly using high temperature materials. A double-walled tubular structure has at least one helical strip of superconductive material on the inner wall of the inside tube. Brittle, non-ductile superconducting materials may be used. A coolant, typically liquid nitrogen, is circulated between the tubes to maintain the superconductor below the critical temperature of the superconductor. A buffer layer is preferably included between tube wall and superconductor. A plurality of alternating layers of buffer and superconductor may be used.

Abstract: A method of forming a superconducting circuit comprises the steps of preparing a ceramics body which is changed from a non-superconductive phase not superconducting at the working temperature into a superconducting phase superconducting at the working temperature by heat treatment and performing the heat treatment on a part of the ceramics body by applying a laser beam to the ceramics body to change the same into the superconductive phase, thereby to form a superconducting circuit consisting of the superconductive phase and the non-superconductive phase on the ceramics body.

Abstract: The present invention relates to novel multi-layer composite solid state membranes which are capable of separating oxygen from oxygen-containing gaseous mixtures at elevated temperatures. The membranes comprise a multicomponent metallic oxide porous layer having an average pore radius of less than about 10 micrometers and a multicomponent metallic oxide dense layer having no connected through porosity wherein the porous and dense layers are contiguous and such layers conduct electrons and oxygen ions at operating temperatures.

Abstract: An inverted MISFET structure with a high transition temperature superconducting channel comprises a gate substrate, an interfacial layer with one or more elements of the VIII or IB subgroup of the periodic table of elements, an insulating layer and a high transition temperature superconducting channel. An electric field, generated by a voltage applied to its gate alters the conductivity of the channel.

Abstract: This invention relates to a process for restoring permeance of an oxygen-permeable ion transport membrane utilized to recover oxygen from an oxygen-containing gaseous mixture which contains water, carbon dioxide or volatile hydrocarbons. The process utilizes a class of ion transport membranes formed from multicomponent metallic oxides wherein permeance of such membranes had been believed to be permanently degraded by water and the like under conventional process operating temperatures. This invention provides a continuous process for restoring oxygen permeance of such membranes caused by deleterious interaction between the membrane and components such as carbon dioxide, water or hydrocarbons at elevated process temperatures.

Abstract: A metal electrode formed on an oxide superconductor for electric connection to the oxide superconductor, includes a first layer of Ag in direct contact with the oxide superconductor, and a second layer formed on the first layer. The second layer is formed of noble metal excluding Ag. The metal electrode can be formed by forming a first layer of Ag to cover a whole surface of the oxide superconductor layer, and forming a second layer of noble metal excluding Ag, to cover a whole surface of the first layer, thereby to form a double metal layer, and patterning the double metal layer so as to form a metal electrode composed of the double metal layer.

Abstract: A superconducting device has an oxide superconducting material with a passivation or blocking film formed on its surface. The film helps to maintain a uniform oxygen concentration of the superconducting material through its thickness. The superconducting material is thus superconductive throughout its cross-section, and particularly in the vicinity of the surface bearing the film.

Abstract: A superconductor structure having a substrate, the substrate defining a surface. Applied to the surface of the substrate is a barrier layer. Applied to the barrier layer is a layer of superconductive material comprising copper and oxygen. The barrier layer serves to prevent the interaction of the superconductive material with the substrate, thus destroying the stoichiometry of the superconductive material and resulting in a loss or decrease in superconductivity. A protective layer is, optionally, applied to the layer of superconductive material.

Abstract: A method for fabricating an active device comprises the steps of injecting particles into a single crystal substrate of a semiconductor material at a predetermined depth from the surface, annealing the substrate that contains the particles to form an insulator layer within the substrate, generally in correspondence to the predetermined depth, the step of annealing including a step of forming a single crystal semiconductor layer of a semiconductor material identical in composition with the substrate, on the insulator layer that is formed by the annealing, starting a deposition of a layer of an oxide superconductor on the semiconductor layer, growing the oxide superconductor layer while maintaining an epitaxial relationship with respect to the substrate; and converting the semiconductor layer to an oxide layer simultaneously to the growth of the oxide superconductor layer.

Abstract: A thin-film superconducting LC network comprising a dielectric substrate having first and second oppositely disposed surfaces, a first thin-film superconducting conductor on one of the surfaces defining an inductor, second and third thin-film superconducting conductors on said first and second surfaces, respectively, said second and third conductors opposing each other and having at least a portion of the dielectric substrate therebetween to form a capacitor, and thin-film superconducting conductor for interconnecting the inductor and capacitor to form a desired LC network. In one embodiment, the substrate between the second and third conductors have a thickness less than the thickness of the substrate between the first conductor and it oppositely disposed surface. In another embodiment, the inductor is defined by a plurality of closely spaced adjacent turns and a channel is disposed within the substrate between the adjacent turns.