Abstract: An annular end piece for a cylindrical vacuum vessel, comprising a metal end piece (42); an outer decorative shell (44) spaced away from a surface of the metal end piece; and a layer of solid foam filling the space between the metal end piece and the outer decorative shell.

Abstract: Low field SQUID MRI devices, components and methods are disclosed. They include a portable low field (SQUID)-based MRI instrument and a portable low field SQUID-based MRI system to be operated under a bed where a subject is adapted to be located. Also disclosed is a method of distributing wires on an image encoding coil system adapted to be used with an NMR or MRI device for analyzing a sample or subject and a second order superconducting gradiometer adapted to be used with a low field SQUID-based MRI device as a sensing component for an MRI signal related to a subject or sample.

Abstract: A superconducting wire, a method of manufacturing the superconducting wire, an antenna coil and a NMR system are disclosed. At least a superconducting material, a paramagnetic material and a diamagnetic material are closely attached and integrated with each other to form a longitudinally continuous wire. The paramagnetic material and the diamagnetic material are arranged in such a manner that the magnetic properties of the paramagnetic material and the diamagnetic material substantially offset each other in the longitudinal and diametrical directions. A superconducting layer is exposed to a part or the whole of the outer periphery of the wire. A low-resistance material layer is formed inside the superconducting layer.

Abstract: A superconducting magnetism measuring apparatus is provided which is capable of favorably measuring a faint degree of magnetism generated in the cervical or waist part of a subject to be measured with no need of the neck or waist of the subject being bent forward. Its sensor cylinder (10) is arranged of a four-sided cylindrical shape having a width along the y direction of not smaller than 5 cm and not greater than 20 cm and a width along the x direction of not smaller than 5 cm and not greater than 20 cm. One side at the distal end (10c) of the sensor cylinder (10) is moderately curved to project at the center not smaller than 0.5 cm and not greater than 4 cm from both the upper and lower ends along the y direction.

Abstract: The invention relates to a method for producing a superconductive element to be used as a wire-in-channel superconductor in magnetic resonance imaging (MRI) and in nuclear magnetic resonance (NMR) applications, which superconductive element contains a superconductive wire and a copper component having a longitudinal groove and the superconductive wire being positioned in the groove. In order to produce the wire-in-channel superconductive element by a mechanical contact between the superconductive wire and a wall of the groove in the copper component, at least one contact surface is coated with a lead free solder material before having the mechanical contact. In order to enhance the thermal and electrical conduction and to create a bond between the said components the soldering material is fused in annealing process step.

Abstract: A biomagnetic field measurement apparatus according to the present invention comprises: a head part provided with SQUID sensors (Superconducting Quantum Interference Device) for measuring a magnetocardiogram, the sensors being arranged in a row in a right and left direction at a lower end portion of the head part and being spaced apart by a predetermined space, and a non-magnetic liquid coolant container for cooling the SQUID sensors; an electronic circuitry part for controlling the SQUID sensors and measuring a signal; a signal processing software part for acquiring and storing the signal detected by the electronic circuitry part to a PC, calculating the signal and thus transforming the signal to a magnetic signal or a current signal, then mapping and displaying the transformed signal; and a bed part made of a non-magnetic material, mounted at a lower side of the head part to be spaced apart therefrom and provided with a platy sliding bed for measuring a magnetocardiogram by using the SQUID sensors of the he

Abstract: A method of making a superconductor device is described.

Abstract: A radio-frequency (RF) resonator system, in particular, for a magnetic resonance (MR) probe, comprising at least one RF resonator with a substrate, on which a conductive structure is applied, wherein the conductive structure comprises regions of capacitive and inductive elements, is characterized in that the conductive structure is coated at least in the regions of the capacitive elements with at least one dielectric layer that covers the regions of the capacitive elements at least partially, wherein the local thickness of at least one of the dielectric layers is set in dependence on the resonance frequency of the uncoated RF resonator, on a defined resonance frequency of the resonator once it is coated, on the dielectric constant of the substrate and on the dielectric constant of the materials of the dielectric layers.

Abstract: An inspection apparatus capable of suppressing degradation of oxide superconductors comprises a transformer including a flux-change detection coil and a flux transmission coil and formed of a first superconductor, an SQUID element magnetically connected to the flux transmission coil and formed of a second superconductor, a first indirect cooling section containing the flux transmission coil and the SQUID element, a second indirect cooling section including a first through hole, the flux-change detection coil winding around the first through hole, a vessel including a second through hole formed therein and located inside the first through hole, the vessel making, a sealed space, a space in which the transformer and the SQUID element are located, and a cooling section thermally connected to the first and second indirect cooling sections to cool the transformer and the SQUID element to a value not higher than the critical temperatures of the first and second superconductors.

Abstract: Disclosed is a measuring structure for a magneto encephalographic equipment superconducting magnetic-shield comprising a vacuum-tight body comprising an outer enclosure wall, a first inner enclosure wall inserted in the outer enclosure wall to define an upper closed space, and a second inner enclosure wall to define a lower open space. The first and second inner enclosure walls are arranged with the bottom of the first inner enclosure wall facing the ceiling of the second inner enclosure wall. A first enclosure of high critical temperature superconductor and a second enclosure of high permeability material are concentrically arranged in the annular vacuum space defined between the first and second inner enclosure walls and the outer enclosure wall.

Abstract: A scanning SQUID microscope is set forth to provide improved output imaging. The SQUID microscope includes a vertically adjustable housing adapted to securely retain a SQUID loop or sensor. A scanning stage of the SQUID microscope is adapted to support a sample while moving the sample along a predetermined path to selectively position predetermined portions of the sample in close proximity to the SQUID loop or sensor to permit the loop or sensor to detect predetermined magnetic field information provided by the predetermined portions of the sample. A position control processor coupled to the scanning stage is operative to receive and process the predetermined magnetic field information to provide corresponding position noise information. Criteria are also presented for determining the expected level of position noise under given experimental conditions.

Abstract: A Superconducting Quantum Interference Device (SQUID) is disclosed comprising a pair of resistively shunted Josephson junctions connected in parallel within a superconducting loop and biased by an external direct current (dc) source. The SQUID comprises a semiconductor substrate and at least one superconducting layer. The metal layer(s) are separated by or covered with a semiconductor material layer having the properties of a conductor at room temperature and the properties of an insulator at operating temperatures (generally less than 100 Kelvins). The properties of the semiconductor material layer greatly reduces the risk of electrostatic discharge that can damage the device during normal handling of the device at room temperature, while still providing the insulating properties desired to allow normal functioning of the device at its operating temperature. A method of manufacturing the SQUID device is also disclosed.

Abstract: In a SQUID magnetometer, high resolution, a high slew rate, and a high dynamic range are achieved without using expensive circuit components having a large number of processing bits and enabling a high speed processing operation. A digital FLL circuit using a double counter system is provided. This circuit utilizes two or more counters, for example, a change range counter in a digital FLL for carrying out a processing operation at a high speed and a reproducing counter in a control/measuring computer. In addition, in the present invention, hysteresis characteristics having a 1?0 positive margin is used. That is, a change of a state of a magnetic flux is counted by means of a counter. At the time of this change, control is made so as to track a different channel between cases in which a magnetic flux increases and decreases, thereby stabilizing the control.

Abstract: Metal complexes comprising a substituted inden-1-yl group or hydrogenated or partially hydrogenated derivative thereof, said group being substituted at least at the 2-position thereof with a C4-30 ligand group containing a secondary or tertiary substitution pattern at the ?-carbon thereof, polymerization catalysts; and olefin polymerization processes using the same are disclosed.

Abstract: The present invention discloses a quantum system comprising computational elements, consisting of an insulated ring of superconductive material, and semi-closed rings, which are used as an interface or input/output facility between the quantum bit and the external world. Faraday induction is used to provide electromagnetic coupling between adjacent computational elements and between the computational elements with interface elements of the quantum system. Therefore the corresponding magnetic flux acts as an information carrier. Ferromagnetic cores are used to improve the magnetic coupling between adjacent elements of the quantum system.

Abstract: A scanning SQUID microscope for acquiring spatially resolved images of physical properties of an object includes a SQUID sensor arranged in perpendicular to the plane of the object under investigation for detecting tangential component of the magnetic field generated by the object. During scanning of the SQUID sensor over the object under investigation, the position signal from a position interpreting unit, as well as relevant output signals from the SQUID sensor are processed by a processing unit which derives from the data, spatially resolved images of the physical properties of the object. The specific orientation of the SQUID sensor with respect to the plane of the object permits an enlarged area of the SQUID chip on which the modulation and feedback line can be fabricated in the same technological process with the SQUID sensor. Additionally, larger contact pads afforded provide for lower contact resistance and ease in forming contact with bias and read-out wires.

Abstract: A method of using a superconductor to generate energy. The superconductor is alternated between a temperature above and below a critical temperature defined by a transition between the superconducting and non-superconducting state. The superconductor interacts with a magnetic field as the superconductor changes states. Energy is harnessed by coupling with the magnetic field as its strength fluctuates. The method would be particularly suitable for harnessing solar energy in space.

Abstract: The present invention provides an oxide superconductor thick film which is formed on a substrate or a board and has a high Jc and Ic and a method for manufacturing the same. Predetermined amounts of materials containing elements of Bi, Pb, Sr, Ca and Cu are weighed, mixed and subjected to steps of calcining, milling, and drying, and thereafter an organic binder and an organic vehicle are added thereto to prepare a (Bi, Pb)2+aSr2Ca2Cu3Oz, superconductive paste, which is applied to the surface of a substrate or a board in a thickness of 260 &mgr;m or more and dried. Thereafter, the paste is first subjected to burning at temperatures of 835° C. to 840° C. for 100 hours, then pressurization, and further burning at temperatures of 835° C. to 840° C. for 100 hours, thereby preparing an oxide superconductor thick film having a film thickness of 130 &mgr;m or more having a high Jc and Ic.

Abstract: A Josephson junction has inherent resistance which effectively shunts the junction and thereby obviates a separate shunt resistor and thus reduces surface area in an integrated circuit including a plurality of Josephson junctions. The Josephson junction comprises a stacked array of layers of Nb and a superconductor with Tc>9° K having a penetration depth greater than that of Nb, for example NbyTil-yN, with a layer of a conducting material having a resistivity between 200 &mgr;&OHgr;-cm, 1 &OHgr;-cm, such as TaxN in the stack. The Josephson junction can be formed on a supporting substrate such as silicon with a ground plane such as Nb on the substrate and an insulating layer such as SiO2 separating the ground plane from the stacked array.

Abstract: A scanning SQUID microscope for acquiring spatially resolved images of physical properties of an object includes a SQUID sensor arranged in perpendicular to the plane of the object under investigation for detecting tangential component of the magnetic field generated by the object. During scanning of the SQUID sensor over the object under investigation, the position signal from a position interpreting unit, as well as relevant output signals from the SQUID sensor are processed by a processing unit which derives from the data, spatially resolved images of the physical properties of the object. The specific orientation of the SQUID sensor with respect to the plane of the object permits an enlarged area of the SQUID chip on which the modulation and feedback line can be fabricated in the same technological process with the SQUID sensor. Additionally, larger contact pads afforded provide for lower contact resistance and ease in forming contact with bias and read-out wires.

Abstract: A solid state dc-SQUID includes a superconducting loop containing a plurality of Josephson junctions, wherein an intrinsic phase shift is accumulated through the loop. In an embodiment of the invention, the current-phase response of the dc-SQUID sits in a linear regime where directional sensitivity to flux through the loop occurs. Changes in the flux passing through the superconducting loop stimulates current which can be quantified, thus providing a means of measuring the magnetic field. Given the linear and directional response regime of the embodied device, an inherent current to phase sensitivity is achieved that would otherwise be unobtainable in common dc-SQUID devices without extrinsic intervention.

Abstract: A solid-state quantum computing structure includes a set of islands that Josephson junctions separate from a first superconducting bank. A d-wave superconductor is on one side of the Josephson junctions (either the islands' side or the bank's side), and an s-wave superconductor forms the other side of the Josephson junctions. The d-wave superconductor causes the ground state for the supercurrent at each junction to be doubly degenerate, with two supercurrent ground states having distinct magnetic moments. These quantum states of the supercurrents at the junctions create qubits for quantum computing. The quantum states can be uniformly initialized from the bank, and the crystal orientations of the islands relative to the bank influence the initial quantum state and tunneling probabilities between the ground states.

Abstract: A solid-state quantum computing structure includes a d-wave superconductor in sets of islands that clean Josephson junctions separate from a first superconducting bank. The d-wave superconductor causes the ground state for the supercurrent at each junction to be doubly degenerate, with two supercurrent ground states having distinct magnetic moments. These quantum states of the supercurrents at the junctions create qubits for quantum computing. The quantum states can be uniformly initialized from the bank, and the crystal orientations of the islands relative to the bank influence the initial quantum state and tunneling probabilities between the ground states. A second bank, which a Josephson junction separates from the first bank, can be coupled to the islands through single electron transistors for selectably initializing one or more of the supercurrents in a different quantum state. Single electron transistors can also be used between the islands to control entanglements while the quantum states evolve.

Abstract: A gradiometer integrating pickup coils comprises pickup coils 11Xp, 11Xn magnetically connected to a SQUID through associated input coils 2, and pickup coils 11Yp, 11Yn magnetically connected to a SQUID through associated input coils 2, respectively. Two superconducting loops are connected in series to each of the SQUIDs, when viewed from Josephson junctions 5. The input coils 2 form superconducting closed loops together with the pickup coils 11Xp, 11Xn, 11Yp, 11Yn associated therewith. The SQUIDs are respectively connected to form an 8-figured shape as a whole such that currents flow in two superconducting loops of each SQUID in opposite directions to each other, with respect to the application of a uniform field, in order to reduce environmental magnetic field noise.

Abstract: A superconducting thin film pattern (20) formed from an oxide superconducting thin film is formed on a sapphire substrate (10) having a step (11) via a CeO2 buffer layer, and the step (11) and superconducting thin film pattern (20) are formed such that the step (11) crosses a predetermined portion of a square thin film pattern (22) having an opening portion (23) at the central portion. Step-edge Josephson junctions (26, 27) are formed at the portion crossed by the step (11), and a SQUID is obtained. The sapphire substrate is relatively inexpensive, and a large substrate can be used.

Abstract: An apparatus and method for measuring a second-order gradient of a magnetic field using a super conductor quantum interference device (SQUID) which obtains the second-order gradient of the magnetic field with a simple-constructed and low-priced measuring apparatus having three SQUID sensors and one differential circuit only.

Abstract: A superconducting current measuring circuit is provided with a detection loop through which a current flows by the influence of a magnetic field generated by a measurement target current. The detection loop contains a superconductor. The superconducting current measuring circuit is also provided with a superconducting sampler circuit for measuring the current flowing through the detection loop.

Abstract: A SQUID made of an oxide superconducting thin film is formed on a sapphire substrate. CeO2 film, RBa2Cu3O7−x film (“R” indicates a rare earth element chosen among a group formed of Yb, Er, Ho, Y, Dy, Gd, Eu, Sm and Nd) and SrTiO3 film are deposited on the substrate top of the sapphire substrate successively. Furthermore, an oxide superconducting thin film to form a SQUID is deposited on the SrTiO3 film.

Abstract: The present invention relates to a SQUID made of an oxide superconducting thin film is formed on a sapphire substrate. CeO2 film, RBa2Cu3O7−x film (“R” indicates a rare earth element chosen among a group formed Yb, Er, Ho, Y, Dy, Gd, Eu, Sm and Nd) and SrTiO3 film are deposited the substrate top of sapphire successively. Furthermore, an oxide superconducting thin film to be a SQUID is deposited on the SrTiO3 film.

Abstract: This magnetic sensor comprises a flux transformer 2 having a superconducting thin film 2f formed on a sapphire substrate 2s, and a SQUID 1 disposed on the flux transformer 2 opposite thereto. In this magnetic sensor, since the sapphire substrate 2s, which can be obtained in a large size, is used for the flux transformer 2, even when the SQUID 1 is made smaller, the magnetic flux introduced from the flux transformer 2 into the SQUID 1 can be enhanced so as to increase the effective magnetic flux capturing area, whereby the detecting performance is improved, while the manufacturing cost can be reduced due to the smaller size of the SQUID 1.

Abstract: An asymmetric planar gradiometer for use in making biomagnetic measurements. The gradiometer is formed from a magnetometer which is inductively-coupled to the smaller of two connected loops patterned in a superconducting film which form a flux transformer. The magnetometer is based on a SQUID formed from a high T.sub.c superconducting material. The flux transformer and magnetometer may be formed on separate substrates, allowing the baseline to be increased relative to presently available devices.

Abstract: The present invention comprises a high-transition-temperature superconducting device having low-magnitude low-frequency noise-characteristics in magnetic fields comprising superconducting films wherein the films have a width that is less than or equal to a critical width, w.sub.C, which depends on an ambient magnetic field. For operation in the Earth's magnetic field, the critical width is about 6 micrometers (.mu.m). When made with film widths of about 4 .mu.m an inventive high transition-temperature, superconducting quantum interference device (SQUID) excluded magnetic flux vortices up to a threshold ambient magnetic field of about 100 microTesla (.mu.T). SQUIDs were fabricated having several different film strip patterns. When the film strip width was kept at about 4 .mu.m, the SQUIDs exhibited essentially no increase in low-frequency noise, even when cooled in static magnetic fields of magnitude up to 100 .mu.T.

Abstract: A magnetic sensor comprises a SQUID made of a superconducting thin film. The superconducting thin film has a washer pattern and a terminal portion. The washer pattern has a non-square one hole pattern and a pair of slit patterns. The hole pattern has rectangle shape and includes the center of the washer pattern. The slit patterns having a straight shape growing parallel to the long side of the hole pattern, from the outside edge of the washer pattern toward the inside of the washer pattern. This outside edge of the washer pattern is the nearest to the hole pattern. There is an artificial grain boundary in the domain that spacing between the hole pattern and the slit pattern is narrowest. There is no artificial grain boundary in the other domain at all.

Abstract: A circuit device for driving a SQUID magnetometric sensor. This device includes an FLL magnetometer circuit for driving the SQUID with an AC signal as a magnetometric sensor, an evaluator circuit for evaluating the SQUID characteristics, and a selector circuit for selecting a sensor function or an evaluator function. When the selection circuit selects one of the sensor and evaluator functions, only one of magnetometer and evaluator circuits is activated. Therefore, the circuit device can act alternatively as either a sensor or an evaluator.

Abstract: Pickup coils constructed by superconductors and a SQUID part are formed on a single substrate. The pickup coils are parallelly connected to two other superconductors (inductance of the SQUID ring) in a SQUID ring, which consists of two Josephson junctions and two superconductive lines. Each of the superconductors can be a superconductive line of one loop or a washer type coil. Each pickup coil occupies about one half of the area of the substrate and the SQUID and the pickup coils are symmetrical with respect to the center line of the substrate.

Abstract: An oxide film having a desired pattern is first formed on a magnesia substrate. A superconducting oxide film is then formed on the exposed portion of the magnesia substrate and also on the oxide film. Thus, a tilt-boundary junction is formed in the boundary between the superconducting oxide film portion on the magnesia substrate and the superconducting oxide film portion on the oxide film. The tilt-boundary junction functions as a Josephson junction. By utilizing the Josephson junction in the tilt-boundary junction, a SQUID pattern can be formed on the magnesia substrate to provide a SQUID device.

Abstract: A SQUID 10 was multiple junctions, each junction allowing a critical current to flow therethrough. The SQUID 10 comprises a laminar structure including: (a) a substantially planar substrate 12; (b) a first high temperature superconductive layer 14 of substantially uniform thickness deposited on the substrates; (c) a dielectric layer 16 deposited on the first superconductive layer 14, the dielectric layer 16 comprising a planar level segment 18 having two ramp segments defining SQUID junctions at opposing ends 20 and defining SQUID hole; and (d) a second high temperature superconductive layer 24 of substantially uniform thickness deposited on the dielectric layer 16, the second high temperature superconductive layer 24 covering all three segments of the dielectric layer 16.

Abstract: A nondestructive inspection apparatus having a SQUID is made with compact configuration and is capable of detecting a metallic or non-metallic metal for defects, corrosion, and the like, by forming the SQUID and a magnetic field applying coil on the same substrate. The SQUID comprises two Josephson junctions, a washer coil connected to the Josephson junctions to form a superconducting loop, shunt resistors, a damping resistor, and a feedback modulation coil, all of which are formed from a superconducting thin film on a supporting substrate. A magnetic field applying coil is formed on the same supporting substrate with a superconducting thin film or a normal conducting metal thin film. The magnetic field applying coil, which generally has plural turns around the SQUID, applies a dc or ac magnetic field to a sample. The change in magnetic field caused by a defect in the sample is detected by the washer coil, and the position and size of the defect may thus be determined.

Abstract: A three-terminal device constructed from a Josephson junction with one or more asymmetric control lines is disclosed. The device is constructed with high temperature superconducting materials. The junction can be a bicrystal, SNS (Superconducting-Normal-Superconducting) or any other type of high temperature superconductor junction. The control line is either a conducting or superconducting material which is electrically isolated from the junction but inductively coupled into the junction. A portion of the control line is approximately directly above the junction and has current which at least partially flows parallel or nonparallel to current flowing across the junction. The control line current alters the magnetic field within the junction which changes the critical current of the junction. The junction is in a superconducting or resistive state depending on whether the bias current of the junction is greater than or less than the control current.

Abstract: Superconductivity is inhibited in selected portions of a high temperature superconductor ("HTS") material by patterning the selected portions with a resist. The patterned material is ion-bombarded to implant impurity ions in non-resist-bearing portions of the material. After low temperature annealing, the non-resist-bearing portions of the material lose their superconducting characteristics, but such characteristics are preserved in the material's resist-bearing portions. The material's crystalline structure is preserved, so additional layers can be epitaxially grown atop the inhibited material. Superconductivity is inhibited at a selected depth in a HTS material by subjecting the material to impurity ion bombardment at an energy level controlled to implant ions in the material at the selected depth. After low temperature annealing, the material loses its superconducting characteristics at the selected depth, but such characteristics are preserved at other depths (i.e.

Abstract: A measurement system for measuring material deterioration in accordance with a magnetic field of the material in the presence of radiation. The measurement system includes a detection circuit which detects a magnetic field of the material and generates a signal indicative thereof which signal includes noise due to the radiation, a signal processing circuit including semiconductor devices to process the signal generated from the detection circuit and a noise reducing circuit for at least reducing noise in the generated signal which is due to the radiation. The signal processing circuit is installed at a place where a dose equivalent of radiation is equal to or smaller than that of a place where the detection circuit is installed.

Abstract: A low-noise directly coupled dc SQUID magnetometer is disclosed. The magnetometer provides for single layer fabrication and is particularly applicable to high-T.sub.c superconductors operating at 77 Kelvin. A pair of dc SQUIDs are connected and biased in series such that the output voltage modulation with applied flux of the dual SQUID magnetometer, is double that of a single SQUID magnetometer. The bias current is applied to one SQUID and removed from the second SQUID of the pair. The magnetometer pick-up coil is directly coupled to the SQUID pair, providing for coherent modulation of the series-connected SQUIDS and a reduction of flux density noise of the device by a factor of 1/.sqroot.2.

Abstract: The SQUID device consists of a loop of superconducting film material applied to the face of a substrate, the loop having a first width. A Josephson Junction is formed in the loop of the superconducting film material by pads of superconducting film material overlying one another and separated by a layer of insulating material. The pads have a second width larger than the first width. To increase the gain and improve the signal-to-noise ratio, the SQUID device may include a plurality of SQUID loops connected to one another in parallel. These loops may be overlie one another, or be adjacent to one another, or both, and may be either conventional SQUID loops or the improved SQUID loops with wide pads.

Abstract: A superconducting magnetoresistive element has superconducting portions having a high critical current density and weak-coupling portions having a low critical current density. The superconducting portions and weak-coupling portions are alternately arranged and connected in series. The superconducting magnetoresistive element is fabricated, for example, by forming semiconductor films at a plurality of sites on a substrate in a manner that the semiconductor films are spaced from each other, then forming a superconducting thin film all over the substrate and processing the superconducting thin film into a line pattern which passes over the plurality of semiconductor films, and heat-treating the substrate to diffuse a constituent element of the semiconductor films in the superconducting thin film. Portions of the superconducting thin film overlying the semiconductor films become the weak-coupling portions and the rest portions of the superconducting thin film become the superconducting portions.

Abstract: A DC SQUID has a first washer coil for forming a superconducting ring, Josephson junctions and a dampening resistor coupled to both ends of the first washer coil, and a shunting resistor connected in parallel to the Josephson junctions. An input coil is magnetically coupled with the first washer coil, and a first modulation coil is also magnetically coupled with the first washer coil. A ground plane comprising a superconducting film is disposed to cover an area of the Josephson junctions without covering the first washer coil for shielding the Josephson junctions from a magnetic noise. The ground plane prevents a magnetic flux trap from occurring, thus enabling stable operation of the DC SQUID. A washer cover comprising a superconducting film is disposed to cover only a slit portion of the first washer coil to prevent leakage of a magnetic field from the slit portion. The ground plane and the washer cover are simultaneously formed in a same layer of the DC SQUID.

Abstract: A flux transformer comprises a pickup coil 1, an input coil 2 and a pair of lines 3, 4. The line 4 contains a bridge part 4a intersecting the input coil 2. The pickup coil 1, input coil 2 and a pair of lines 3, 4 are formed of a first and a second oxide superconducting thin films 11, 13. Furthermore, the flux transformer comprises a non-superconducting thin film 12. The non-superconducting thin film 12 is disposed between the first and the second oxide superconducting thin films 11, 13 and is located in a domain wherein the line 4 intersects the input coil 2. A pattern of the first oxide superconducting thin film 11 corresponds to the pickup coil 1, the input coil 2 and the lines 3,4 except the bridge part 4a. The pattern of the second oxide superconducting thin film 13 corresponds to the input coil 2 except the domain where the non-superconducting thin film exits, the pickup coil 1 and the lines 3,4.

Abstract: A magnetometer comprises a magnetic field pickup coil and a magnetic field detector that receives electrical signals from the pickup coil and produces an electrical detector output responsive thereto. The pickup coil and detector, which are preferably made of high temperature superconductors, are enclosed in an insulated enclosure having no vacuum insulation structure. Preferably, the enclosure is made of a foamed polymer material such as styrofoam. A coolant is provided to the interior of the enclosure, to cool the pickup coil and detector to a temperature below their superconducting transition temperature. A number of such modular magnetometers may be connected together to form an array.

Abstract: A magnetic flux microscope that measures the magnetic field about a sample surface. The apparatus uses a thin-film superconducting quantum interference device (SQUID) as the scanning device. Magnetic shielding is provided about the SQUID and is held stationary relative to the SQUID. The apparatus and method provides a very high magnetic image of the sample with a very high spatial and field resolution.

Abstract: A biomagnetometer includes a magnetic field sensor unit having a magnetic field pickup coil. A vessel contains the sensor unit. The vessel includes a flexible contact face with the magnetic field sensor unit mounted in the interior of the vessel adjacent to the flexible contact face. Insulation at the flexible contact face of the vessel prevents excessive heat flow through the flexible contact face. Pickup units using this structure can be connected together into flexible or rigid arrays. In operation, the pickup coil is cooled to a temperature of less than its superconducting transition temperature. A detector measures the magnitude of magnetic fields sensed by the sensor unit.

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.