Abstract: The invention relates to a measuring instrument for time-variable magnetix fluxes, or flux gradients, to electrical resistance elements, and to a measuring system comprising a measuring instrument or electrical resistance element according to the invention. The core component of the measuring instrument is a flux transformer composed of a base material which has a phase transition to the superconducting state. According to the invention, even when the base material is in the superconducting state, this flux transformer comprises at least one load region having electrical resistance that is other than zero for dissipating the electric energy in the conductor loop thereof. For this purpose, according to the invention the conductor loop and the magnetic field source are disposed in one plane and are typically photolithographically structured. The resistance elements according to the invention, having resistance values of ?10?4?, are used as core components in the measuring instrument.

Abstract: A magnetic detection coil made of a single wire is constructed of one of superconducting and metallic materials. Four second-order differential coils are arranged so that a geometric figure obtained by connecting the respective centers of the four differential coils can form a parallelogram. By providing intersections between the four second-order differential coils, the values of magnetic flux respectively penetrating the differential coils are differentiated in three different directions.

Abstract: A magnet system for generating a magnetic field may include a superconducting magnet, a switch, and a heater element thermally coupled to the switch. The superconducting magnet is structured to generate magnetic fields, and the switch includes a non-inductive superconducting current carrying path connected in parallel to the superconducting magnet. In general, the switch is structured to only carry a level of current that is a portion of the current required to obtain a full field by the superconducting magnet.

Abstract: There, is provided a directly-coupled high-temperature superconductor SQUID magnetic sensor in a single thin film structure, which suppresses flux trapping or jumping generated in the sensor in a magnetic field, prevents the degradation in performance of the SQUID sensor, and operates stably with high sensitivity even in the magnetic field. The SQUID magnetic sensor including a bi-crystal substrate 1 having a bi-crystal grain boundary, pickup loops 7a-7d formed from a first high-temperature superconducting thin film on the bi-crystal substrate 1, and a SQUID ring 3 formed from the first high-temperature superconducting thin film on the bi-crystal grain boundary, directly connected with the pickup loops 7a-7d, wherein a plurality of pickup loops 7a-7d are disposed equally spaced from a bi-crystal grain boundary line 2 so as not to overlap with the bi-crystal grain boundary.

Abstract: The invention relates to a SQUID system having an increased flux voltage transfer function. The object of disclosing a circuit configuration providing an increased flux voltage transfer function of a SQUID, wherein the measurement sensitivity of the system is noticeably increased and the required readout electronics are simplified, is achieved in that at least one SQIF is provided as an amplifier circuit and is connected downstream of the first SQUID, wherein a coupling coil electrically connected to the first SQUID is directly associated with all loops of the SQIF.

Abstract: A magnetic screening system uses directional gradiometers with high resolution and accuracy to measure magnetic field signatures of target objects (e.g., gun, knife, cell phone, keys) in a volume of interest. The measured signatures can be compared to signatures of known objects stored in a local database. Various mathematical processes may be used to identify or classify target object signatures. In a network of magnetic screening systems, the magnetic screening systems can transmit signatures to a central signature database, and a management computer can share the central signature database with all of the magnetic screening systems on the network. The magnetic screening system can operate in multiple modes, such as a tracking mode, measurement mode, and self-test mode. Through use of unique processes and designs, the magnetic screening system can achieve a high rate of processing persons for target objects.

Abstract: A receiver system (18) for an electromagnetic prospecting system is disclosed. The electromagnetic prospecting system comprises a transmitter for transmitting a primary electromagnetic field so as to generate a secondary electromagnetic field from a terrain that is being prospected, the secondary electromagnetic field having a transient, decaying time domain profile. The receiver system (18) comprises first and second sensors (20, 22) for detecting the secondary electromagnetic field, wherein the second sensor (22) is less sensitive than the first sensor (20) so as to detect the secondary electromagnetic field over a first time period, with the first sensor (20) being used to detect the secondary electromagnetic field after the first time period. Typically, each sensor (20, 22) comprises three orthogonal SQUID magnetometers, with the second sensor (22) being approximately 10 times less sensitive than the first sensor (20).

Abstract: Oxide semiconductor thin film transistors (TFT) and methods of manufacturing the same are provided. The methods include forming a channel layer on a substrate, forming source and drain electrodes at opposing sides of the channel layer, and oxidizing a surface of the channel layer by placing an oxidizing material in contact with the surface of the channel layer, reducing carriers on the surface of the channel layer. Due to the oxidizing agent treatment of the surface of the channel layer, excessive carriers that are generated naturally, or during the manufacturing process, may be more effectively controlled.

Abstract: The present invention provides a probe-type SQUID system to detect magnetic particles stored in the living organisms or magnetic-labeling indicators for immunoassays and tumor or other applications. The probe-type SQUID system comprises a probe union, a SQUID union and a connecting electrically conducting wires such as copper wires, wherein the probe union is coupled with a cooling module such as TE cooler module to avoid power heating so that the probe can approach to the living organism to detect magnetic particles with high-sensitivity.

Abstract: A magnetic detection coil is provided, which includes a plurality of differential coils. Each differential coil is made of one of superconductors and metallic materials. The differential coils having mutually different loop directions are arranged in parallel at a spatially predetermined distance apart and mutually electrically connected in series. Each differential coil is one of a first-order differential coil and a second-order differential coil.

Abstract: SQUIDs may detect local magnetic fields. SQUIDS of varying sizes, and hence sensitivities may detect different magnitudes of magnetic fields. SQUIDs may be oriented to detect magnetic fields in a variety of orientations, for example along an orthogonal reference frame of a chip or wafer. The SQUIDS may be formed or carried on the same chip or wafer as a superconducting processor (e.g., a superconducting quantum processor). Measurement of magnetic fields may permit compensation, for example allowing tuning of a compensation field via a compensation coil and/or a heater to warm select portions of a system. A SQIF may be implemented as a SQUID employing an unconventional grating structure. Successful fabrication of an operable SQIF may be facilitated by incorporating multiple Josephson junctions in series in each arm of the unconventional grating structure.

Abstract: There is provided a nondestructive inspection apparatus using a SQUID magnetic sensor which allows nondestructive and accurate detection of magnetic particles in an insulator such as an electronic device or in a magnetizable member. The nondestructive inspection apparatus using the SQUID magnetic sensor comprises: a magnet for horizontal magnetization 4, the magnet applying a magnetic field to a specimen in the longitudinal direction of the specimen 3?; an inspection unit on which a specimen 3 is set, the specimen 3 being horizontally magnetized in the longitudinal direction by the magnet for horizontal magnetization 4; and belt conveyers 2, 5 for conveying the horizontally magnetized specimen 3; and a gradiometer 8 for detecting a particle horizontally magnetized along with a magnetizable member as the horizontally magnetized specimen 3.

Abstract: A method of searching for a material fated to generate an interband phase difference soliton includes the steps of generating an AC in a soliton candidate material, identifying a loss of AC magnetic susceptibility of the siliton candidate material due to a turn and a twist cut of a vortex line and judging whether or not the soliton candidate material is capable of generating soliton.

Abstract: 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 a 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 HTSC 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. A head-accommodating area is delimited by the hollow partition between, the bottom of the first inner enclosure wall and the ceiling of the second inner enclosure wall both facing each other, and a plurality of SQUID sensors are arranged in the upper closed space, encircling the head-accommodating area.

Abstract: Multiple SQUID magnetometers that include at least two SQUID loops, each of which is composed of at least two Josephson Junctions connected in parallel with superconducting wires, are provided. The SQUID loops are fabricated such that they share a common Josephson Junction. Devices and application that employ the multiple SQUID magnetometers are also provided.

Abstract: A persistent-mode magnet, assembled from superconducting annuli, provides a micro coil NMR, in which compactness and manufacturability are provided for a variety of applications. An annular magnet for micro NMR can include a YBCO-annulus Helmholtz coil, for example, that can energized by a magnet system and then transported for use at a second location with an operating system.

Abstract: The present invention discloses a novel magnetic sensor device performing direct magnetic field imaging, comprising a probe having a conical tip portion which is configured as a sensor having two superconductors separated by a thin non-superconducting layer (such as a Josephson junction based sensor), where the non-superconducting layer is located at the apex portion of said conical tip, thereby defining electron tunneling region(s) at said apex portion. The technique of the present invention enables the sensor device to be very small and to be brought very close to the sample surface.

Abstract: A device comprises a mixed sensor design with at least one superconducting loop (1) containing at least one constriction (3) and a magneto-resistive element (2) located next to the constriction (3). The device contains at least one heating element (5) that allows switching at sufficiently high frequency of at least one part of the superconducting loop (1) above its critical temperature, such that the super-current flowing through the at least one constriction (3) containing the at least one magneto-resistive element (2) is temporarily suppressed.

Abstract: Methods and processes for determining the particle size distribution of metal catalysts are provides. Superconducting Quantum Interference Device (SQUID) magnetometer is used to evaluate the magnetic catalyst particle sizes dispersed in the support material. Dependence on variation of the metal/support material ratio, which defines the metal particle sizes, the catalyst can show paramagnetic, superparamagnetic, and ferromagnetic behaviors.

Abstract: A compact, solid-state THz source based on the driven Josephson vortex lattice in a highly anisotropic superconductor such as Bi2Sr2CaCu2O8 that allows cw emission at tunable frequency. A second order metallic Bragg grating is used to achieve impedance matching and to induce surface emission of THz-radiation from a Bi2Sr2CaCu2O8 sample. Steering of the emitted THz beam is accomplished by tuning the Josephson vortex spacing around the grating period using a superimposed magnetic control field.

Abstract: A composite sealed vessel is provided. The vessel includes a non-metallic, generally cylindrical inner containment piece, a non-metallic, generally cylindrical outer containment piece disposed around the inner containment piece. A pair of non-metallic flanges are disposed at ends of the inner and outer containment pieces to form a closed structure defining a cavity therein. The vessel also includes a metallic external lining disposed over the closed structure to form a leak-tight pressure boundary.

Abstract: The invention relates to a SQUID arrangement for measuring a change in a magnetic field, the change in the magnetic field being caused by a specimen that is arranged in a magnetization field and the SQUID arrangement including a direct current SQUID. In order to provide a simple design in which the losses in the magnetic flux are also simultaneously minimized, it is provided that the SQUID itself is embodied for generating the magnetization field.

Abstract: A measuring container is provided, which can be used for biomagnetic measurements, in particular for magnetocardiological measurements. The measuring container comprises an outer screen against electromagnetic high frequency fields and an inner screen against low frequency electromagnetic fields. The measuring container is constructed as a two-chamber system with an outer container comprising the outer screen. A measuring chamber with the inner screen is introduced into the outer container. An antechamber which can be walked into from outside is formed between the inner wall of the outer container and the measuring chamber.

Abstract: An innovative method is provided for assessing structural integrity of a sample. The method comprises: capturing a signal indicative of magnetic flux density caused by an Eddy current flowing in the sample; extracting an envelope of the captured signal using a demodulation scheme; sampling the envelope at a frequency that is lower than the frequency of the excitation current signal which generated the Eddy current; and examining the sampled envelope to assess structural integrity of the sample.

Abstract: A CAM (current arrow map) 71 and another CAM 72 are obtained from magnetocardiogram waveforms measured from both front and back sides of a subject using data at a point of time of an R-wave peak, then the coordinates of the CAM 72 are inverted in both x and y axis directions to obtain a CAM 73. The coordinates of each of the CAMs 71 and 73 are converted to polar coordinates to obtain CAMs 74 and 75 at both front and back sides of the subject. After that, the CAM 74 is adjusted to the CAM 76 in scale to obtain a CAM 76 , and CAMs 74 and 76 are combined. Then, the CAM data at measuring points on each measuring-points-missing radius vector is inserted through an arithmetic processing by interpolation so that CAM data at every measuring point on a planispheric chart 77 are connected to each another consecutively.

Abstract: Provided is a highly accurate optical pumping magnetometer, in which a static magnetic field and an oscillating field to be applied to a vapor cell are stabilized. To this end, the optical pumping magnetometer includes: Helmholtz coils for applying a constant static magnetic field to a vapor cell serving as a magnetic field detector; fluxgate magnetometers for detecting environmental magnetic noise in two directions of X-axis direction and Y-axis direction other than Z-axis direction which is a direction for detecting a magnetic field coming out of a measurement object while locating the vapor cell in the center thereof; magnetometer drive circuits for driving the fluxgate magneotometers; current converters for converting outputs of the magnetometer drive circuits into amount of currents; and magnetic field generating coils for generating a magnetic field in a phase opposite to the environmental magnetic noise in the two directions.

Abstract: Geometries for superconducting sensing coils for SQUID-based systems are described, such as a superconducting sensing coil with a flat washer shape the inner diameter of which has an extension which is a small fraction of the extension of the outer diameter. Also described are a second-order gradiometer comprising such coils and a superconducting sensing coil structure comprising an external low-melting point metallic loop encapsulating one or more superconductive coil loops, together with a heterogeneous superconductive sensing wire for gradiometers, consisting of an internal copper skeleton surrounded by an external lead-tin alloy.

Abstract: Apparatus for determining magnetic properties of materials comprises a portable probe (1), an equipment trolley (2) holding cryogenics and electronics and connecting cables (3). The probe (1) comprises a drive coil (4) and a correction coil (5), the drive coil (4) being disposed symmetrically with respect to an inner second-order gradiometer sensor coil (8). Electrical connectors in the form of 2-metre long Belden (1192A) microphone cables (3) are used to connect the apparatus on the equipment trolley (2) to the drive coil (4), the correction coil (5) and the sensor coil (8). The drive coil (4) is driven so as to generate a sinusoidally varying magnetic field. The electronics comprise a flux-locked loop (9), a SQUID controller (10), a data acquisition module (11), which captures and processes the signals and a computer (12). A liquid-nitrogen dewar (13) is supported on the equipment trolley (2) and houses a sensitive SQUID detector (14) and a transfer coil (15) made from copper.

Abstract: It is an aspect of the present invention to provide a magnetic detection coil 1b made of a single wire of one of superconducting and metallic materials. Four second-order differential coils 21 to 24 are arranged so that a geometric figure obtained by connecting the respective centers of said four differential coils can form a parallelogram. By providing intersections 25 to 27 between said four second-order differential coils 21 to 24, the values of magnetic flux respectively penetrating said differential coils 21 to 24 are differentiated in three different directions. The present invention is able to detect magnetic signals stably, despite a current direction of the signal source.

Abstract: A magnetic characteristics measurement system includes a superconducting quantum interference device which detects a magnetization of a sample located in the vicinity of a superconducting pickup coil and outputs an electrical signal representing the magnetization. A coil is disposed to surround the superconducting pickup coil and is connected to an AC power supply so as to generate an alternating magnetic field. The AC signal output from the superconducting quantum interference device is sampled by use of an A/D converter which is operable in an audio frequency range and outputs a digital signal corresponding to the AC signal. Phase adjustment is performed so as to optimally correct a time shift of the digital signal in relation to a reference voltage signal. The phase-adjusted signal is subjected to Fourier transformation processing so as to detect harmonic components as magnetic characteristics.

Abstract: The invention relates to an MRT device with a superconducting magnet whose coils are located in a helium tank and with electronic control components whereby a section of control components is located inside the helium tank or the helium tank has a hollow depression in its outer surface in which a section of the control components is located. The invention also relates to an MRT device with a superconducting magnet whose coils are located in a helium tank which is located in a vacuum vessel and with electronic control components whereby the helium tank has a hollow depression in its outer surface and whereby the vacuum vessel has a further hollow depression in its outer surface which is located in the area of the hollow depression in the helium tank whereby a section of the control components is located in the further hollow depression in the vacuum vessel.

Abstract: A measuring device includes a magnetic shielding part for shielding an outer magnetic field, and a plurality of magnetic field sensors which are arranged in a shielding space which is formed by the magnetic shielding part, wherein the magnetic field sensor includes a plurality of magnetic field collection mechanisms which collect magnetic fields which the beam current to be measured generates, and the magnetic field collection mechanism is a cylindrical structural body which has at least a surface thereof formed of a superconductive body and includes a bridge portion which has only a portion thereof formed of a superconductive body on an outer peripheral portion thereof, and a magnetic field which the beam current to be measured generates is measured by the magnetic field sensors. Due to the arrangement of the plurality of magnetic field sensors, a beam position and a beam current can be detected.

Abstract: A method and device for field detection are provided, in which one or more gradiometers (31, 32, 33) are positioned in the field and rotated about their axes. Rotation of a single gradiometer allows an output signal of the gradiometer to be analyzed in the Fourier domain, which allows particular field components to be obtained, and also separates the field signal from noise, in the frequency domain. Use of three such rotating gradiometers with non-parallel axes allows a complete magnetic field gradient tensor to be obtained with data redundancy, and can reduce crosstalk.

Abstract: The present invention provides a current sensor capable of sensing a current to be detected with high precision while realizing a compact configuration. The current sensor includes a first MR element including element patterns disposed at a first level, a second MR element including element patterns disposed at a second level, and a thin film coil which winds at a third level provided between the first and second levels while including winding body portions extending in an X axis direction in correspondence with the element patterns of the first and second MR elements, and which applies a current magnetic field to each of the element patterns when a current to be detected is supplied. Therefore, by using both of the first and second MR elements, the current magnetic field can be detected with high sensitivity and high precision.

Abstract: The present invention provides a compact current sensor capable of measuring a current to be detected with high precision. A current sensor includes: a first magnetoresistive element including a plurality of element patterns which extend in an X axis direction at a first level, are disposed so as to be adjacent to each other in a Y axis direction orthogonal to the X axis direction, and are connected in parallel with each other; and a thin film coil which includes a plurality of winding body portions extending in the X axis direction in correspondence with the element patterns and winds at a second level different from the first level, and applies a current magnetic field to each of the element patterns when a current to be detected is supplied. Therefore, the absolute value of the resistance change amount in the magnetoresistive element increases. While realizing a compact configuration, the current to be detected, flowing in the thin film coil can be measured with high precision.

Abstract: A non-destructive testing method of improved efficiency. Two one-dimensional images are obtained by scanning an optical line over an object to be tested in an X- and Y-directions each for one scan in lieu of conducting a prior art method of two-dimensionally scanning a optical spot on the object to be tested. A two-dimensional image is reconstructed from the obtained two one-dimensional images. Since only two relative scans between the object to be tested and the optical line is necessary, scanning time is remarkably shortened in comparison with that of the prior art.

Abstract: A superconducting magnetic field detection element (10) comprising at least one superconducting pick-up loop (12) formed on a common flexible substrate (11), wherein the common flexible substrate (11) is in a non-planar position, such that the at least one superconducting pick-up loop (12) is operable to detect magnetic fields of differing orientation.

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 induced magnetic field detecting apparatus of the present invention is configured so as to irradiate laser light onto an inspection target from the same side as the side on which a pickup coil for magnetic field detection is disposed and be able to perform irradiation of the laser light and detection of a magnetic field induced by the irradiation of the laser light on the same side relative to the inspection target. Furthermore, the induction magnetic field detection apparatus of the present invention adopts a configuration in which laser light is irradiated onto the inspection target through the inside of the loop-shaped pickup coil set up inside the container. This configuration exerts an effect of being able to detect a feeble magnetic field with higher accuracy.

Abstract: A reference-current optimizing apparatus of a Reference Junction Double Relaxation Oscillation SQUID (RJ-DROS) with a signal SQUID and a reference junction for detecting a magnetic flux signal is provided. The reference-current optimizing apparatus includes a voltage controller for converting a digital signal into an output voltage; a buffer for receiving the output voltage and preventing a current generated in the RJ-DROS from flowing inversely into the reference-current optimizing apparatus; a low-pass filter for eliminating a noise mixed in an output voltage of the buffer; and a resistor for converting an output voltage of the low-pass filter into a current and providing both ends of the reference junction with the current. The reference-current optimizing apparatus may also include a preamplifier having a number of junction bipolar transistors.

Abstract: It is possible to simplify the cooling mechanism of a superconductor, significantly reduce the cost, simplify the measurement work, and reduce the time required for measurement. A beam current meter includes: a cylindrical super conductor beam current sensor arranged in a vacuum vessel in such a manner that the beam incoming into the vacuum vessel is guided to pass through a bore of the vacuum vessel and a bridge portion is formed at the outer diameter, a SQUID arranged at the bridge portion of the beam current sensor; a cylindrical superconductor magnetic shield arranged so as to surround the external diameter side of the beam current sensor in such a manner that the SQUID is positioned between the beam current sensor and the magnetic shield, so that a beam is guided to pass through the bore of the beam current sensor, thereby measuring the beam the beam current of the beam. The beam current meter uses a freezing device as cooling means for cooling the beam current sensor, the SQUID, and the magnetic shield.

Abstract: There is provided a magnetic shield which can shield external magnetic fields in the direction of an axis of a tubular magnetic shield and in the direction vertical to the axis. A magnetic shield has a cylindrical ferromagnetic substance 2-1 having openings on both ends and two superconducting loops housed in the respective insides of superconducting loop containers 1-1, 1-2. The superconducting loops are constructed of high critical temperature superconducting wire. The two superconducting loops have semicircle shapes and are arranged in x-direction so as to be symmetrical with respect to an axis of the cylindrical ferromagnetic substance 2-1. The superconducting loop containers 1-1, 1-2 are arranged in the insides near both open ends of the cylindrical ferromagnetic substance 2-1 with supports 20. The superconducting loops are arranged to be vertical to the axis of the cylindrical ferromagnetic substance 2-1. The superconducting loops are cooled by liquid nitrogen or a refrigerator.

Abstract: In a helium 3 refrigerator-utilizing magnetic property measurement system which enables magnetization measurement to be effected till 0.3 K by utilizing the formerly proposed magnetic property measurement system (MPMS), a main pipe 23, for the object of enabling magnetization measurement to be infallibly effected even when the upper limit of magnetic field the MPMS can induce is applied, includes an upper supporting tube 41 positioned in the uppermost part and allowing a bellows 28 to be connected to the lateral part thereof, a condensing tube 42 supported first in the lower part of the upper supporting tube, an outer tube 44 fixed in the lower part of the condensing tube and adapted to form an outer wall of an insulated vacuum chamber 43 formed between the outer tube and a lower inner tube 45 forming an inner wall of the insulated vacuum chamber 43. In each of the tubes, the lower inner tube 45 is formed of titanium.

Abstract: A superconductive quantum interference device (SQUID) system is provided for measuring the alternating current (AC) magnetic susceptibility of material at a single frequency or a mixing frequency from multiple frequencies, such as mf1+nf2, where f1 and f2 are two excitation frequencies of two primary coils. The system includes a magnetic-flux sourcing unit for producing an AC magnetic flux on a sample and a magnetic-flux reading unit for reading the induced magnetic flux from the sample via a magnetic flux transformer. The magnetic-flux reading unit includes a SQUID set for detecting the induced magnetic flux, so as to obtain the magnetic susceptibility of the sample in converting calculation.

Abstract: The present invention relates to a method of controlling the characteristics of a double relaxation oscillation SQUID having a reference junction. In the method of controlling characteristics of a reference junction-type double relaxation oscillation SQUID (RJ-DROS) having a signal SQUID and a reference junction, a reference DC current flows through the reference junction in order to control the characteristics of the DROS. A modulation width of an averaged relaxation voltage, which reacts to a magnetic flux, may be controlled at the reference junction. An amount (modulation depth) of an averaged relaxation voltage, which reacts to a magnetic flux, may be controlled at the reference junction. An amount of an operation application current may be controlled at the reference junction. Accordingly, the reference current of the reference junction can be changed by causing the current to flow through the reference junction.

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: An instrument for measuring sub-pico Tesla magnetic fields using a superconducting quantum interference device (SQUID) inductively coupled to an unshielded gradiometer includes a filter for filtering magnetically-and electrically coupled radio frequency interference (RFI) away from the SQUID. This RFI is principally coupled to the SQUID via the unshielded gradiometer. The filter circuit includes a resistor-capacitor (RC) combination interconnected to first and second terminals so that it is parallel to both an input coil of the SQUID and the gradiometer. In addition, a shielding enclosure is used to electromagnetically shield the filter circuit from the SQUID, and a method is employed to increase the impedance between the input coil and the SQUID without diminishing the overall sensitivity of the instrument.

Abstract: A biomagnetic field measurement apparatus capable of easily bringing the sensor planes close to the head surface of the subject and capable of detecting cerebral magnetic fields of the left brain and the right brain simultaneously with a higher sensitivity is provided by disposing two independent cryostats holding SQUID fluxmeters in the mirror image relation to each other. The two cryostats move vertically and horizontally and rotate while interlocking with each other and maintaining the mirror image relation to each other. A gantry holding the cryostats has a function of suppressing vibration of the cryostats and has a gate shape.

Abstract: There is provided a biomagnetic field measurement apparatus capable of carrying out exact positioning work and highly sensitive signal detection. To bring a sensor surface close to a body surface while the sensor surface and the body surface are kept parallel, a cryostat is constructed so as to be capable of oscillating and expanding and contracting. A gantry is formed by three supports. A first support is a portal support that supports the whole of the gantry. A second support is supported on the first support, and is rotatable with a first direction being the axis. A third support is supported on the second support, and is movable in the axial direction of the cryostat as viewed from the second support. The cryostat is supported on the third support, and moves integrally with the third support.

Abstract: An apparatus for controlling and adjusting the magnetic state of a magnetic probe for detecting magnetic signals of a sample, it employs a negative feedback control unit to counter the change of magnetization of the magnetic probe. The local magnetic field of the sample influences the magnetization of the magnetic probe. Through the feedback coil inductively coupled to the magnetic probe, the variation of magnetization of the magnetic probe is compensated by the magnetization induced by the feedback coil. This apparatus is capable of reducing the magnetic interaction between the magnetic probe and sample. Meanwhile, a current bias unit is used for adjusting the magnetization of the magnetic probe to an arbitrary value. This capability allows a scanning probe microscope applying this invention to manipulate magnetic objects.