Abstract: A coil for a magnet includes a superconductor comprising a Bi2Sr2CaCu2O8+? (Bi-2212) high temperature superconductor (HTS) filament. The HTS filament can be encased in a protective conducting sheath. The superconductor is wound to form a coil. A reinforcement winding is wound with the superconductor. The reinforcement winding can be a wire, a tape, a band, and an outer layer encasing the superconductor filament. A method of making a coil for a magnet, a composite superconductor for a magnet, and a magnet are also disclosed.

Abstract: An electromagnetic sensor for use in a variety of applications requiring extremely high sensitivity, such as measuring power and characteristics of incident electromagnetic radiation includes a superconducting layer that carries an exchange field for providing a spin splitting effect of charge carriers in the superconducting layer, a metal electrode, and an insulating layer arranged between the superconducting layer and metal electrode to form a spin filter junction therebetween. The electromagnetic sensor provides an antenna including a wave collecting element, in contact with the superconducting layer to convey thereinto external electromagnetic waves that are generated by an external source.

Abstract: Use, as a component with variable inductance which is a function of the current passing through it, of an inductive superconductive component having at least two terminals and comprising at least one line segment working with said terminals and integrating at least one of these terminals, this line segment constituting a conductive or superconductive layer within a stack of films alternately superconductive and insulating.

Abstract: In a wall of a package base made of aluminum or aluminum alloy, there is formed a through-hole, through which a semi-rigid coaxial cable passes. A central conductor of the semi-rigid coaxial cable is joined to an electrode with a solder material. The semi-rigid coaxial cable has an insulating material through which the central conductor passes and an outer conductor provided therearound. The central conductor and outer conductor are made of stainless steel, for example, and the insulating material is made of fluororesin, for example. Inside the through-hole, the wall of the package base and the outer conductor are electrically connected to each other via a stainless material within the hole formed in a cylindrical fluororesin material. The semi-rigid coaxial cable and the like are fixed to the wall with a conductive screw.

Abstract: Intermodulation distortion (IMD) is known to be an impediment to progress in superconductor-based filter technology. The present invention's methodology for reducing IMD can open doors to heretofore unseen practical applications involving high temperature superconductor (HTS) filters. Typical inventive practice includes (a) increasing the thickness d, and/or (b) changing the operation temperature T, of the filter's HTS film. The film's thickness d is increased in such a way as to decrease the IMD power PIMD in accordance with the material-independent proportionate relationship PIMD?1/d1.5-6. The film's operation temperature T is bettered or optimized in accordance with the material-independent proportionate relationship PIMD?(?O(T))10(K(2)(T))2/(?O(T))6, and further in accordance with three individual material-dependent relationships, namely, between operation temperature T and each of linear penetration depth ?O, gap maximum ?O, and kernel K(2).

Abstract: This invention provides a laser trimming method for tuning the frequency of a spiral resonator, and for improving the characteristics of a high temperature superconductor filter comprised of high temperature superconductor spiral resonators, by tuning the individual high temperature superconductor spiral resonators. This invention also provides a method for tuning the resonance frequency of a high temperature superconductor planar coil. This invention also provides a laser ablation process for creating high temperature superconductor circuit elements.

Abstract: An electrode is steeped in a solution of Mg and B and a negative voltage is applied to the electrode so as to precipitate superconductive MgB2 on the electrode. Superconductive MgB2 is easily manufactured in various forms and at low costs without any special device.

Abstract: Novel structures and methods for forming useful high temperature superconducting devices, most particularly resonators, are provided. Structures resulting in reduced peak current densities relative to known structures achieve numerous desirable benefits, especially including the reduced intermodulation effects of earlier resonators. In one aspect of this invention, a spiral in, spiral out resonator is provided, characterized in that it has an odd number of long runs, at least equal to five long runs, where the long runs are connected by turns, and wherein there are at least two sequential turns of the same handedness, followed by at least two turns of the opposite handedness. In yet another aspect of this invention, it has been discovered that reducing the size of the input and output pads of HTS resonators increases the relative inductance compared to the capacitance. Yet another resonator structure is a spiral snake resonator having a terminal end disposed within the resonator.

Abstract: A compact superconducting filter device can easily change a bandwidth and a center frequency without changing a pattern or shape of the filter. A filter pattern is formed on a substrate made of a dielectric material. The filter pattern is made of a superconductor material. A signal input line and a signal output line are formed on the substrate so as to extend from a periphery of the filter pattern. An adjust plate is located above the filter pattern with a predetermined distance therebetween. The adjust plate is formed of one of an electrically conductive material, a superconductive material and a dielectric material.

Abstract: A superconducting filter including input/output feeders formed on one surface of a dielectric substrate, resonator patterns formed on one surface of the dielectric substrate, and a dielectric plate mounted on the one surface of the dielectric substrate with a plurality of spacers formed on said one surface of the dielectric substrate disposed therebetween. The dielectric plate covers the region including the resonator patterns, and the input/output feeders length-wise over the length within ±20% of positive integer times a ¼ effective wavelength from the sides nearer to the resonator patterns.

Abstract: The present invention relates to superconductive filter technology. According to the arrangement of the superconductive filter (1), a columnar resonating member (23) having a superconductive material formed on the surface thereof is attached at one of its ends thereof to an inner wall (22) of a filter housing (21) so that a space is interposed between the columnar resonating member and each of connectors (27a, 27b) which are connectable to a signal input/output cables (5a, 5b), respectively. According to this arrangement, heat conduction from the outside can be suppressed as far as possible, and the superconductive condition can be created with stability, with the result that a stable filtering characteristic can be created.

Abstract: A method and apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.

Abstract: A resonator is formed by forming a microstrip line having an electrical length corresponding to a ?/2 wavelength on a dielectric substrate, forming both side portions of the microstrip line from the center thereof into spiral shapes, making the orientations of the spirals opposite each other, making outer-side portions of the spiral shapes on both sides, inclusive of the central portion of the microstrip line, linear in shape overall, and making linear in shape a portion of prescribed range from the end portion of each spiral shape.

Abstract: A method for reducing ac loss in a superconducting coil of cable-in-conduit type superconductor made from chrome-coated compound superconducting strands, characterized in that when a superconducting coil is produced by the wind-and-react technique, bending or twist strain is applied in an amount of 0.15˜0.3% to the conductor cable portion after it has been heat-treated to form the superconducting compound, thereby separating the individual superconducting strands the chrome coat on which sintered as the result of heat treatment and further characterized in that the applied bending or twist strain is thereafter reverted to 0.1% or less, thereby reducing the ac loss of the superconducting coil.

Abstract: A resonator for use in a radio frequency filter including a substantially planar resonant portion that is substantially elliptical in plan. The resonant portion is mounted on a dielectric substrate. The resonator is configured to operate in at least a mode in which resonance occurs with a radial current and with substantially no current along the edge of the resonant portion. A filter comprising a plurality of the resonators is also disclosed.

Abstract: A superconducting magnetic energy storage (SMES) device including a first coil made of superconducting material, a cooling mechanism for cooling the first coil to superconducting temperatures, a second coil inductively coupled to the first coil for inputting emergy to, and/or outputting energy from, the first coil, and a switch for switching the first coil between a superconducting condition and a non-superconducting condition. The first coil is arranged as a closed loop electric circuit having no connecting device mechanically connected to it for inputting or outputting energy. The switch includes a third coil for the application or removal of a magnetic field for switching the first coil between its non-superconducting and superconducting conditions. A method inputs energy to and/or outputs energy from the first coil and a power supply system utilizes the device and method.

Abstract: A tunable filter having a fixed substrate, a first and second plate comprising a high-temperature superconductor material on the fixed substrate, a movable substrate, a mechanical driver attached to the fixed substrate and the movable substrate, a floating plate comprising a high-temperature superconductor material on the fixed substrate wherein the floating plate, the first plate, and the second plate define a gap, and wherein the gap is varied by length changes in the mechanical driver is provided.

Abstract: Novel structures and methods for forming useful high temperature superconducting devices, most particularly resonators, are provided. Structures resulting in reduced peak current densities relative to known structures achieve numerous desirable benefits, especially including the reduced intermodulation effects of earlier resonators. In one aspect of this invention, a spiral in, spiral out resonator is provided, characterized in that it has an odd number of long runs, at least equal to five long runs, where the long runs are connected by turns, and wherein there are at least two sequential turns of the same handedness, followed by at least two turns of the opposite handedness. In yet another aspect of this invention, it has been discovered that reducing the size of the input and output pads of HTS resonators increases the relative inductance compared to the capacitance. Yet another resonator structure is a spiral snake resonator having a terminal end disposed within the resonator.

Abstract: A superconducting signal transmission apparatus provided with a vacuum container 11, a superconducting electronic device 12 provided in the vacuum container 11, an input side transmission line 13 and output side transmission line 14 for connection to the superconducting electronic device 12 through the vacuum container 11, and a cooling mechanism (15, 16, 17) for cooling the superconducting electronic device 12 and further having a heat cutoff signal transmission unit 20 inserted at least at part of the input side and output side transmission lines 13 and 14. The heat cutoff signal transmission unit 20 is comprised of a substrate 31 and a flat circuit body 30 provided with a signal transmission line 32 and ground layer (33, 33-1, 33-2). The substrate 31 is comprised of a dielectric material having a small heat conductivity. The conductor portions forming the signal transmission line 32 and the ground layer are formed with thin thicknesses enabling suppression of the inflow of heat from the outside.

Abstract: A circuit is provided wherein the electronic properties of the circuit are varied by a magnetic actuator. The circuit includes a fixed substrate and a movable substrate. The magnetic actuator comprises a magnetic driver on an upper surface of the fixed substrate that is substantially overlapped by an HTS reaction plate on the lower surface of the fixed substrate. A tuning current applied through a continuous strip of HTS material in the magnetic driver induces a repulsive magnetic force causing the movable substrate to move with respect to the fixed substrate.

Abstract: The present invention relates to superconductive filter technology. According to the arrangement of the superconductive filter (1), a columnar resonating member (23) having a superconductive material formed on the surface thereof is attached at one of its ends thereof to an inner wall (22) of a filter housing (21) so that a space is interposed between the columnar resonating member and each of connectors (27a, 27b) which are connectable to a signal input/output cables (5a, 5b), respectively. According to this arrangement, heat conduction from the outside can be suppressed as far as possible, and the superconductive condition can be created with stability, with the result that a stable filtering characteristic can be created.

Abstract: A tunable filter having a fixed substrate, a first and second plate comprising a high-temperature superconductor material on the fixed substrate, a movable substrate, a mechanical driver attached to the fixed substrate and the movable substrate, a floating plate comprising a high-temperature superconductor material on the fixed substrate wherein the floating plate, the first plate, and the second plate define a gap, and wherein the gap is varied by length changes in the mechanical driver is provided.

Abstract: A closed conductive loop for use in planar circuits to realize shunt capacitors instead of conductive patches is disclosed. The closed conductive loop may be formed on a planar substrate or extend to multiple conductive layers in a multi-layer circuit. The use of closed conductive loops as shunt capacitors offers possibilities of more flexible circuit layout, reduced circuit footprint and comparable or improved performance as compared to using conductive patches as shunt capacitors.

Abstract: A device and method for tuning a planar filter through a wide range of center frequencies are disclosed. The tuning assembly includes a superconductive tuning tip and an actuator configured and adapted to move the tuning tip through a sufficient range of distances from a resonator or a portion thereof to vary the resonant frequency of the resonator by at least about 10% of the untuned frequency in at least one increment of 0.01% or smaller. An actuator and a position-sensor can be employed in a closed loop feedback system to control the position of the tuning tips. The present invention also provides a method of tuning a filter that includes moving a tuning tip through a sufficient range of distances from a resonator to vary the resonant frequency of the resonator by at least about 10% in at least one increment of 0.01% or smaller.

Abstract: A method includes providing a superconducting material having pinning sites that can pin magnetic vortices within the superconducting material. The method also includes pinning one or more magnetic vortices at one or more of the pinning sites. An information storage apparatus includes a superconducting material, doped particles within the superconducting material that can pin dipole magnetic vortices, a magnetic tip that generates pinned magnetic vortices and a magnetic detector that detects pinned magnetic vortices.

Abstract: A metal complex composition containing complexes having metal species of a rare earth element, barium and copper and ligands of a trifluoroacetic acid or pentafluoropropionic acid ligand, a pyridine ligand and an acetylacetone ligand. A superconductive film may be obtained by applying an organic solvent solution of the above metal complex composition to a substrate and by heat treating the coating.

Abstract: A filter circuit includes a first resonator and a second resonator each having a different resonance frequency. The first resonator is included in a first block, and the second resonator is included in a second block. The first block further includes a first delay unit connected to the first resonator. An input terminal divides an input signal to the first block and the second block. An output terminal combines signals passing through the first block and the second block and outputs the combined signal. The first delay unit converts a phase difference between the signals passing through the first block and the second block to reverse-phase or nearly reverse-phase.

Abstract: High temperature superconductor mini-filters and mini-multiplexers utilize self-resonant spiral resonators and have very small size and very low cross-talk between adjacent channels.

Abstract: A dual operation mode all temperature filter is provided. The dual operation mode filter is provided with a housing defining at least two cavities, an input port and an output port. It is also provided with a non-superconducting resonator disposed in a first one of the cavities and a superconducting resonator disposed in a second one of the cavities. The second resonator comprises a superconducting material containing 8-15% silver. The dual operation mode filter filters at a relatively high level at temperatures below a threshold temperature and at a lower, conventional level, at temperatures below the threshold.

Abstract: A superconductor on-chip microstrip line (2, 4) to off-chip microstrip line (7) transition of low characteristic impedance (15, 20, 22) is realized that obtains a bandwidth of 200 GHz for MCM application while employing solder bump (15, 17) technology to connect the chips (3, 5) to the off-chip microstrip and substrate (6). Circular openings (20, 22) through the respective ground plane layers (10 & 16) of the off-chip and on-chip microstrips are provided in positions respectively underlying and overlying the solder bump (15) for the signal. The openings may be sized to provide a desired ratio of inductance to capacitance, the larger the size, the greater the ratio value. This technique may be used to match characteristic impedance to give broad bandwidth low impedance interconnections needed for direct SFQ chip-to-chip communication on a passive MCM.

Abstract: A tunable filter having a fixed substrate, a first and second plate comprising a high-temperature superconductor material on the fixed substrate, a movable substrate, a mechanical driver attached to the fixed substrate and the movable substrate, a floating plate comprising a high-temperature superconductor material on the fixed substrate wherein the floating plate, the first plate, and the second plate define a gap, and wherein the gap is varied by length changes in the mechanical driver is provided.

Abstract: Multi-stage electric filters with improved intermodulation-distortion characteristics and a method for designing such electric filters is provided. In general, the invention may include a multi-resonator electric filter in which one or more of the resonators have been intentionally designed to have a different IP and/or Q than the other resonators in the electric filter. In one case, the electric filters include a 4-resonator Chebyshev narrow pass-band filter with at least the first resonator having a Q and/or IP different from at least one other resonator in the filter. The filter thereby has improved IMD power over conventional designed filters while maintaining high Q. In a preferred embodiment the filter may include a superconducting material. The relative Q and IP of the respective resonators in the improved filter may depend on the relative strength of in-band and out-of-band signals.

Abstract: A resonator for rf frequencies, especially microwave, in telecommunications systems, with an extremely stable resonant frequency over a desired operating temperature range, of predetermined width (Y) and thickness (X) and having a predetermined length (Z) in the direction of propagation for achieving a desired resonance, comprises a dielectric substrate of rutile, and first and second temperature compensating layers of sapphire on two opposite faces of the substrate and extending along the length of the substrate, these sapphire layers having a predetermined thickness, and first and second superconducting layers formed on the outer surfaces of the temperature compensating layers.

Abstract: A filter device includes a super-conducting type filters connected in series with each other and is accommodated in a vacuum chamber. Operating temperatures of the filters are controlled to different temperatures from the outside of the vacuum chamber independently of each other. Each filter varies its filtering characteristics, particularly its central frequency of pass-band, in correspondence with the operating temperature, while maintaining the same pass-band width. As the filters operated at the different operating temperatures provide different filtering characteristics, the combined or resulting filtering characteristics of the filtering device can be adjusted as desired even after the filtering device is installed at a mobile telecommunication base station.

Abstract: There is disclosed a planar filter which can variably control a pass frequency band with a high precision and which is superior in skirt property and little in ripple. A planar filter member and tuning member are disposed opposite to each other via a predetermined gap. The filter member is structured in such a manner that an input/output portion formed of a superconductor and a plurality of resonance elements are formed on a substrate. The tuning member is structured in such a manner that on the surface of a magnetic plate with a permeability changing by an applied magnetic field, a plurality of dielectric thin films, and a plurality of electrodes for applying electric fields to the dielectric thin films are arranged. Each of the dielectric thin films is disposed in a position opposite to a gap between the resonance elements of the filter member, or a gap between the filter member and the input/output portion.

Abstract: The present invention provides for a method and apparatus to control non-adjacent cross-coupling in a micro-strip filter. In instances of weak cross-coupling, such as a filter circuit on a high dielectric constant substrate material (e.g., LaAIO3 with dielectric constant of 24), a closed loop is used to inductively enhance the cross-coupling. The closed loop increases the transmission zero levels. For strong cross-coupling cases, such as a filter circuit on a lower dielectric constant substrate material (e.g., MgO with dielectric constant of 9.6), a capacitive cross-coupling cancellation mechanism is introduced to reduce the cross-coupling. In the latter instance, the transmission zero levels are moved down.

Abstract: A filter circuit includes a first resonator and a second resonator each having a different resonance frequency. The first resonator is included in a first block, and the second resonator is included in a second block. The first block further includes a first delay unit connected to the first resonator. An input terminal divides an input signal to the first block and the second block. An output terminal combines signals passing through the first block and the second block and outputs the combined signal. The first delay unit converts a phase difference between the signals passing through the first block and the second block to reverse-phase or nearly reverse-phase.

Abstract: In accordance with the present invention, a superconducting phase shift device is presented. The phase shift device can introduce a phase shift between the phases of the order parameters of the device's two terminals. The two terminals can be coupled through an anisotropic superconductor with angled sides, or through two anisotropic superconductors with misaligned phases, or through a ferromagnet in the junction area. The phase shift device can be used in superconducting quantum computing circuitry. A method of fabricating the phase shift device with a technology different from fabrication technology of conventional superconducting materials is described. A method for fabricating a phase shifter chip including an array of phase shift devices is described.

Abstract: A circuit is provided wherein the electronic properties of the circuit are varied by a magnetic actuator. The circuit includes a fixed substrate and a movable substrate. The magnetic actuator comprises a magnetic driver on an upper surface of the fixed substrate that is substantially overlapped by an HTS reaction plate on the lower surface of the fixed substrate. A tuning current applied through a continuous strip of HTS material in the magnetic driver induces a repulsive magnetic force causing the movable substrate to move with respect to the fixed substrate.

Abstract: A microwave device includes a number of parallel-plate resonators that include at least one dielectric substrate and first and second plates arranged on either side of the substrate. At least one of the plates of each of a number of the parallel-plate resonators includes a current interrupting device such that the current lines of at least one undesired mode are interrupted at their maxima to suppress the undesired mode. There is also described a method of interrupting undesired modes in a microwave device having a number of parallel-plate resonators.

Abstract: Multi-stage electric filters with improved intermodulation-distortion characteristics and a method for designing such electric filters is provided. In general, the invention may include a multi-resonator electric filter in which one or more of the resonators have been intentionally designed to have a different IP and/or Q than the other resonators in the electric filter. In one case, the electric filters include a 4-resonator Chebyshev narrow pass-band filter with at least the first resonator having a Q and/or IP different from at least one other resonator in the filter. The filter thereby has improved IMD power over conventional designed filters while maintaining high Q. In a preferred embodiment the filter may include a superconducting material. The relative Q and IP of the respective resonators in the improved filter may depend on the relative strength of in-band and out-of-band signals.

Abstract: A multi-domained bulk REBa2CU3Ox with low-angle domain boundaries which resemble a quasi-single domained material and a method for producing the same comprising arranging multiple seeds, which can be small single crystals, single domained melt-textured REBa2CU3Ox pieces, textured substrates comprises of grains with low misorientation angles, or thick film REBa2CU3Ox deposited on such textured substrate, such seeds being tailored for various REBa2CU3Ox compounds, in specific pattern and relative seed orientations on a superconductor precursor material which may be placed in contact with a porous substrate so as to reduce the amount of liquid phase in the melt. Because seeds can be arranged in virtually any pattern, high quality REBa2CU3Ox elements of virtually unlimited size and complex geometry can be fabricated.

Abstract: A compact dielectric resonator of high Qu, in which an electrode formed of an oxide superconducting material is provided on a surface of the dielectric so as to serve as an electrode. A dielectric filter, dielectric duplexer and a communications device, in which the compact resonator is incorporated, are also provided. The dielectric which constitutes the dielectric resonator of the present invention is preferably a Ba(Mg, Ma)03-based dielectric (wherein Ma is at least one pentavalent elemental metal but cannot be Ta alone), and the oxide superconducting electrode is formed of an oxide superconducting material selected from among a RE—M—Cu—O-based oxide superconducting material (wherein RE is a rare earth element and M is an alkaline earth metal element), a Bi—Sr—Ca—Cu—O-based oxide superconducting material (which encompasses those in which Bi is partially substituted by Pb), and a Tl—Ba—Ca—Cu—O-based oxide superconducting material.

Abstract: The object of the invention is a dual-mode band pass filter consisting of resonators each having a spherically shaped dielectric arranged on at least one high-temperature superconductive film, with a shielding housing, which is arranged over the high-temperature superconductive film and which encloses the dielectric, and with a coupling device for coupling the dipole modes, as well as other coupling and tuning elements.

Abstract: A non-linear transmission line has high temperature superconductive elements periodically loaded thereon. The elements have non-linear characteristics that provide voltage dependent non-linearity to the transmission line. The line can have a circuit with a first layer and a second layer with the second layer having several interdigital circuits printed thereon. The line can also have a meandering configuration or a spiral configuration.

Abstract: In a dielectric resonator, a superconductor is formed on two neighboring surfaces of a cubic dielectric body, and the superconductors formed on each two neighboring surfaces are connected by a silver electrode formed in the vicinity of the edge where the neighboring two surfaces join.

Abstract: A high frequency low loss electrode includes a main conductor and at least one sub-conductors formed along a side of the main conductor. At least one of the at least one sub-conductor has a multi-layer structure in which thin-film conductors and thin-film dielectrics are alternately laminated.

Abstract: The present invention provides for a super-narrow band filter using frequency dependent L-C components. The invention utilizes a frequency dependent L-C circuit with a positive slope k for the inductor values as a function of frequency. The positive k value allows the realization of a very narrow-band filter.

Abstract: Novel structures and methods for forming useful high temperature superconducting devices, most particularly resonators, are provided. Structures resulting in reduced peak current densities relative to known structures achieve numerous desirable benefits, especially including the reduced intermodulation effects of earlier resonators. In one aspect of this invention, a spiral in, spiral out resonator is provided, characterized in that it has an odd number of long runs, at least equal to five long runs, where the long runs are connected by turns, and wherein there are at least two sequential turns of the same handedness, followed by at least two turns of the opposite handedness. In yet another aspect of this invention, it has been discovered that reducing the size of the input and output pads of HTS resonators increases the relative inductance compared to the capacitance. Yet another resonator structure is a spiral snake resonator having a terminal end disposed within the resonator.

Abstract: An HTS microwave circuit has two layers formed with metallic film on a substrate. One layer has a first circuit and another layer has a second circuit, the two circuits being coupled to one another. The second circuit has elements that are incompatible with HTS material such as MEMS technology and flip-chip technology. A microwave switch has a first layer that can carry an RF signal and a second layer that has switch elements that are controlled by a DC. signal. The RF signal and DC signal are isolated from one another. The switch elements include various technologies including a narrow HTS strip. A single layer HTS microwave switch can also be utilized where the switch element is a narrow HTS line. A method of combing HTS technology with incompatible technologies into one device is provided.