Hitachi, Ltd.

International Superconductivity Technology Center

Other

Sharp Kabushiki Kaisha Corporation

Japan Oil, Gas and Metals National Corporation

Mitsui Mineral Development Engineering Co., Ltd.

Superconducting Sensor Technology Corporation

Akira Tsukamoto

Daisuke Suzuki

Akihiko Kandori

Keiichi Tanabe

Kazuo Saitoh

Keiji Tsukada

Kazumasa Takagi

Yoshinobu Tarutani

Tokuumi Fukazawa

Koichi Yokosawa

Seiji Adachi

Yasuo Oshikubo

Kenji Nakanishi

Masahiko Hiratani

Toshikazu Nishino

Tsuyoshi Miyashita

Yusuke Seki

Tsunehiro Hato

Masahiro Yamaoka

Nami Sugita

Masayuki Motoori

Yoshihisa Soutome

Hidehiro Ishikawa

Uki Kabasawa

A magnetic field measuring element includes a Superconducting QUantum Interference Device magnetic sensors, the first sensor disposed either on a second plane perpendicular to a first plane including a coil surface of the third sensor and which includes the center of the third sensor, or in the vicinity of the second plane, and a second sensor disposed either on a third plane perpendicular to the first plane and the second plane, or in the vicinity of the third plane. The center of the first sensor is present either on a straight line which passes through the center of the third sensor and is perpendicular to the first plane, or in the vicinity of said straight line, and the center of the second sensor is present in a position displaced from a line joining the center of the third sensor and the center of the first sensor.

Magnetic field measuring element, magnetic field measuring device, and magnetic field measuring system

A high-temperature superconducting magnetic sensor having superconducting layers formed on a substrate, a superconducting quantum interference device (SQUID) being formed on the superconducting layers, the high-temperature superconducting magnetic sensor includes: a pickup coil that is formed on the superconducting layer and is connected to an inductor of the SQUID; and an input coil that is formed on the superconducting layer, is connected to the inductor of the SQUID and the pickup coil to form a closed loop, and is magnetically coupled with the inductor of the SQUID. In planar view, at least one turn of the input coil surrounds the inductor of the SQUID, or is surrounded by the inductor of the SQUID. The width of the superconductor forming the inductor of the SQUID is 10 &#x3bc;m or less.

High-temperature superconducting magnetic sensor

A magnetic immunoassay system with a mechanism for compensating the direct current residual magnetic field in the vicinity of the specimen measurement position, in a direction perpendicular to the magnetic marker direction of magnetization for the measurement target. This invention reduces the effects of the magnetic field emitted from the unbound magnetic marker due to the residual magnetic field in the specimen solution and detects with high sensitivity the signal of the bound target magnetic marker. The magnetic field at the measurement position is regulated so as to intersect the direction of magnetization of the magnetic marker for the measurement target, in order to make the magnetization direction of the magnetic marker that is unbound due to residual magnetism or remanence in the sample solution, intersect the magnetization direction of the magnetic marker for the measurement target. The signal of the bound target magnetic marker can be therefore measured with high sensitivity since it is isolated from the unbound magnetic marker signal.

Magnetic immunoassay system

A high-temperature superconducting magnetic sensor having a superconducting layer formed on a substrate and a plurality of superconducting quantum interference devices fabricated on the superconducting layer, which includes: a plurality of input coils that are formed on the superconducting layer and connected to or magnetically coupled with each of the plurality of the superconducting quantum interference devices; a pickup coil that is formed on the superconducting layer and connected so as to form a closed loop together with the plurality of the input coils; and a plurality of trimming wires that are formed on the superconducting layer and can be cut off, while making a short-circuit between both ends of each of the plurality of the input coils.

High-temperature superconducting magnetic sensor and fabrication method of the same

Accurate measurement cannot be performed due to magnetic signals from magnetic impurities included in a specimen container. By finding a difference between two measurement signals obtained by applying an external magnetic field for orientation to respective normal and reverse directions, the magnetic signals from the magnetic impurities included in the specimen container which are not dependent on the external magnetic field for orientation can be cancelled. The influence of the magnetic impurities included in the specimen container is reduced, and the signal of the intended bound magnetic marker can be measured with high sensitivity.

Method and system for detection of biomaterials using magnetic marker

The present invention provides an immunoassay technique which enables efficient detection of antigen-antibody reaction with high sensitivity by a magnetic method using magnetic particles and a SQUID magnetic sensor or sensors. A system based on the technique includes a disk-shaped sample holder which holds on a circle a plurality of sample containers for accommodating marked samples, resulting from marking of samples with magnetic particles by antigen-antibody reaction; rotating means for rotating the holder around its central shaft; magnetizing means for magnetizing the marked samples outside a magnetic shield; and a magnetic sensor for detecting, within the magnetic shield, magnetic fields generated from the marked samples which have been magnetized. By rotation of the holder, areas fixing and holding different ones of the sample containers are successively inserted into the magnetic shield, and the magnetization of the marked samples accommodated in first ones of the sample containers and the detection of magnetic fields generated from the marked samples accommodated in second ones of the sample containers are executed in parallel.

Immunoassay system and immunoassay method

A magnetic field measurement system for canceling an external field is provided, in which plurality of sensing magnetometers () for measuring a magnetic field signal in a direction perpendicular to the center axis of a cylindrical magnetic shield () are arranged in two dimensions on a plane parallel to the center axis and a reference magnetometer () for measuring the external field parallel to the center axis as a reference signal is disposed on a plane perpendicular to the plane parallel to the center axis. The reference signal multiplied by a specified factor is subtracted from a difference between signals from the adjacent sensing magnetometers (). The magnetic field measurement system allows measurement of an extremely weak magnetic field by efficiently canceling the external field.

Magnetic field measurement system

An apparatus can detect a magnetic field with a high sensitivity using an ordinary-temperature pickup coil even when the pickup coil is arranged outside a cryostat. Specifically, the apparatus for measuring a magnetic field includes a pickup coil for detecting an external magnetic field, a SQUID electrically or magnetically connected to the pickup coil, a cryostat for holding the SQUID at low temperatures, and a driving device for driving the SQUID. The pickup coil is made of a normal-conducting material and is placed at an ordinary temperature outside the cryostat. By arranging outside the cryostat, the pickup coil can be brought close to a subject and can thereby detect a weak magnetic field in the subject with a high sensitivity.

Apparatus for measuring a magnetic field

A superconductor signal amplifier which receives an extremely small high-frequency signal having a frequency of tens of GHz generated in a superconductive circuit, amplifies the voltage of the high-frequency signal without a decrease in frequency, and outputs the thus amplified high-frequency signal from the superconductive circuit. At an output part of a single flux quantum circuit using a flux quantum as a binary information carrier, there are provided a superconductive junction line for flux quantum transmission and a splitter for simultaneously producing two flux quanta from a flux quantum. According to the number of plural series-connected SQUIDs, a plurality of flux quantum signals are generated and input to the plural series-connected SQUIDs so that the SQUIDs are simultaneously switched to a voltage state. In each SQUID pair comprising two SQUIDs, a part of an inductor is shared by the two SQUIDs for reduction in inductance, thereby increasing an output voltage of the series-connected SQUIDs. Furthermore, a magnetic shielding film formed under each SQUID is electrically isolated from ground to prevent a signal delay due to a parasitic capacitance.

Superconductor signal amplifier

An X-ray, neutron or electron diffraction method, which is devoid of the defects of conventional diffraction apparatus using an imaging plate, which can analyzing a sample, in a non-destructive mode without contact and with a good S/N ratio, even when the sample significantly generates fluorescence or scattered X-rays. The method includes the steps of irradiating a predetermined area of the sample with an X-ray, neutron or electron beam whose axis is oriented at a fixed direction to obtain a diffraction ray, rotating the sample while maintaining the irradiated predetermined area substantially unchanged and while maintaining the angle between the axis of the X-ray, neutron or electron beam relative to the tangential plane of the predetermined area substantially unchanged, forming an image of the diffraction ray from the sample during the rotation of the sample through every predetermined angle using an imaging plate, reading a data of the image formed on the imaging plate to obtain an output data for each rotation of the sample through the predetermined angle, and processing the output data to obtain desired analysis information.

X-ray, neutron or electron diffraction method using an imaging plate and

Disclosed herein is a superconducting field effect transistor (FET) which has at least an active region formed from a film of oxide normal conductor, a plurality of electrodes formed from a film of oxide superconductor, and a means to control the current which flows between the electrodes through the active region. Having a much greater electrode distance than the conventional superconducting device, it can be produced easily by lithography without resorting to special techniques.

Growing community of inventors

Toda, Japan

Akira Tsukamoto