Tdk Corporation

Astellas Pharma Gmbh

Tdk Electronics Company, Limited

Akita Prefecture

Kiyoshi Noguchi

Kei Hirata

Atsushi Yamaguchi

Taro Oike

Yoshihiro Tsuchiya

Tetsuya Roppongi

Masashi Sano

Suguru Takayama

Tomoyuki Sasaki

Hiroshi Ikeda

Isamu Sato

Takahiko Machita

Tohru Oikawa

Shingo Miyata

Koji Shimazawa

Hiraku Hirabayashi

Daisuke Miyauchi

Koji Kobayashi

Satoru Araki

Takamitsu Sakamoto

Toshiaki Izumi

Shin Narushima

Kouji Kobayashi

Tsutomu Chou

Shinji Hara

Migaku Takahashi

Tsutomu Aoyama

Manabu Ohta

Masakiyo Tsunoda

Saori Kajihara

Misao Kohmoto

Makoto Sato

Tomohito Mizuno

Satoshi Miura

Yoshikazu Soeno

Hiroyuki Arioka

Tetsuya Mino

Takuya Adachi

Hironobu Matsuzawa

Seiji Yari

Toshiyuki Ayukawa

Takayoshi Kobuke

Toshio Suzuki

Fumio Maruta

Sayaka Hattori

Daisuke Tenmizu

Yasuhisa Fukunaga

Hisae Shimizu

A magnetic sensor comprises a first ferromagnetic body, a second ferromagnetic body, a channel extending from the first ferromagnetic body to the second ferromagnetic body, a magnetic shield covering the channel, and an insulating film disposed between the channel and the magnetic shield, while the magnetic shield has a through-hole extending toward the channel.

Magnetic sensor, magnetic detector, and magnetic head

The present invention provides a spin injection electrode structure, a spin transport element, and a spin transport device which enable effective spin injection in a silicon channel layer at room temperature. A spin injection electrode structure IE comprises a silicon channel layer, a first magnesium oxide filmA disposed on a first part of the silicon channel layer, and a first ferromagnetic layerA disposed on the first magnesium oxide filmA. The first magnesium oxide filmA partly includes a first lattice-matched part P lattice-matched with both of the silicon channel layerand the first ferromagnetic layerA.

Spin injection electrode structure, spin transport element, and spin transport device

A magnetic sensor comprises a channel, a ferromagnetic body and first and second reference electrodes on the channel, a magnetic shield covering a part of the channel opposing the ferromagnetic body, and an insulating film disposed between the channel and the magnetic shield, while the magnetic shield has a through-hole extending toward the part of the channel opposing the ferromagnetic body.

The magnetic sensor includes a base substrate having a magnetic shield layer; a single-domain semiconductor crystal layer attached via an insulating film on the magnetic shield layer of the base substrate; a first ferromagnetic layer formed on top of the semiconductor crystal layer on the opposite side of the semiconductor crystal layer to the insulating film, via a first tunnel barrier layer; and a second ferromagnetic layer formed, at a distance from the first ferromagnetic layer, on top of the semiconductor crystal layer on the opposite side of the semiconductor crystal layer to the insulating film, via a second tunnel barrier layer.

Spin transport type magnetic sensor

A gap between a main pole and auxiliary pole composing a thin film magnetic head having a microwave assisted function of the present invention is filled with a nonmagnetic dielectric layer to embed a microwave radiator. The nonmagnetic dielectric layer has an inclined surface at a end on a side of an opposing medium surface by which the microwave radiated from the microwave radiator to be bent toward the main pole, whereby the microwave magnetic field generated from the microwave generator can be gathered immediately below the main pole, further improving the microwave assisted effect.

Microwave assisted magnetic head

A microwave oscillation element of the present invention includes a lamination main part in which an oscillating layer that is a magnetization free layer and that generates a high frequency electromagnetic field by an excitation of a spin wave, a nonmagnetic intermediate layer, a polarizer layer, and a reference layer that is to be a base magnetic layer of a spin transfer due to application of current are layered in this order. The oscillating layer is made of CoIr, the polarizer layer is configured of CoCr or CoRu; and the nonmagnetic intermediate layer is configured of Cr or Ru. As a result, the efficiency of the spin injection is improved and the microwave oscillation element where the oscillation efficiency is excellent can be realized.

Microwave oscillating element and thin film magnetic head therewith

A microwave assisted magnetic head of the present invention includes: at least two or more auxiliary coils that are arranged in a periphery of a writing main pole; and microwave current supply means that applies microwave currents to the at least two or more auxiliary coils. The at least two or more auxiliary coils respectively include linear body parts linearly arranged on an ABS side, two of the linear body parts of the at least two or more auxiliary coils are arranged in a substantially orthogonal positional relationship, and the microwave current supply means is configured such that the microwave current supply means changes phase differences of the microwave currents applied respectively to the at least two or more auxiliary coils. Therefore, the microwave current can be easily controlled, and thus, a circularly polarized magnetic field with high magnetization inversion efficiency can be generated as an assistance magnetic field.

Microwave assisted magnetic head and magnetic disk device

The present invention relates to a perpendicular recording magnetic head. A perpendicular recording element includes a main magnetic pole film for emitting a perpendicular magnetic field and is supported by a slider. The main magnetic pole film includes an electrode film and a plated film, the electrode film is an alloy film of at least one element selected from the platinum group and Ni, and the plated film is a magnetic film grown on the electrode film.

Magnetic head with plated magnetic film formed on PdNi alloy electrode film

A magnetic recording and reproducing apparatus includes a metal housing, a magnetic recording medium having a magnetic recording layer, and a thin-film magnetic head having a write magnetic field production unit and a resonance magnetic field production unit. The apparatus further includes a write signal generation unit for generating the write signal, a microwave signal generation unit for generating the microwave excitation signal, a transmission unit for feeding the microwave excitation signal to the resonance magnetic field production unit and for feeding the write signal to the write magnetic field production unit, and a plurality of metal ribs, arranged in the metal housing, for forming a plurality of cavities. Each of the plurality of cavities having a rectangular horizontal section shape and having dimensions to produce no resonance at a frequency of the microwave excitation signal.

Magnetic recording and reproducing apparatus with thin-film magnetic head having microwave magnetic exciting function

A thin-film magnetic head having microwave magnetic exciting function includes a write magnetic field production means for producing, in response to a write signal, a write magnetic field to be applied into a magnetic recording medium, and at least line conductor of a microwave radiator of a plane-structure type, formed independent from the write magnetic field production means, for radiating, by feeding there through a microwave excitation current, a microwave band resonance magnetic field with a frequency equal to or in a range near a ferromagnetic resonance frequency Fof the magnetic recording medium.

Thin-film magnetic head having microwave magnetic exciting function and magnetic recording and reproducing apparatus

An MR element in a CPP structure includes a spacer layer made of Cu, a magnetic pinned layer containing CoFe and a free layer containing CoFe that are laminated to sandwich the spacer layer. The free layer is located below the magnetic pinned layer. The free layer is oriented in a (001) crystal plane, the spacer layer is formed and oriented in a (001) crystal plane on the (001) crystal plane of the free layer. Therefore, in a low resistance area where an area resistivity (AR) of the MR element is, for example, lower than 0.3 &#x3a9;&#xb7;&#x3bc;m, an MR element that has a large variation of a resistance is obtained.

Magnetoresistive effect element in CPP-type structure and magnetic disk device

A thin-film magnetic head having microwave magnetic exciting function, includes a write magnetic field production unit for producing, in response to a write signal, a write magnetic field to be applied into a magnetic recording medium, a line conductor of a microwave radiator of a plane-structure type, formed independent from the write magnetic field production means, for radiating, by feeding there through a microwave excitation current, a microwave band resonance magnetic field with a frequency equal to or in a range near a ferromagnetic resonance frequency Fof the magnetic recording medium, and two conductors separated from the line conductor in a direction perpendicular to a track-width direction of the thin-film magnetic head and parallel to an ABS of the thin-film magnetic head. The microwave radiator is an inverted micro strip waveguide having the line conductor and a ground conductor constituted by the magnetic recording medium. A section of the line conductor, perpendicular to the track-width direction has a rectangular shape. An aspect ratio B/A is within a region from 0.15 to 1.2 or within a region of 7 or more, where A is a length in a lateral direction of the line conductor, which is in parallel with the ABS and perpendicular to the track-width direction, and B is a length in a longitudinal direction of the line conductor, which is perpendicular to the air bearing surface.

A magneto-resistive element includes a lower magnetic shield film and a magneto-resistive film disposed above the lower magnetic shield film. The lower magnetic shield film includes a lower shield layer and an upper shield layer. The upper shield layer is amorphous or microcrystalline, made of a NiFe or CoFe composition containing B or P, and deposited on the lower shield layer. The lower shield layer is a magnetic conductive layer which is amorphous or microcrystalline with a crystal grain size equal to or less than 20 nm.

Magneto-resistive element, thin film magnetic head, magnetic head device, and magnetic recording/reproducing apparatus

A magnetoresistive device with CPP structure, comprising a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed with said nonmagnetic intermediate layer interposed between them, wherein each of said first and second ferromagnetic layers comprises a sensor area joining to the nonmagnetic intermediate layer and a magnetization direction control area that extends further rearward from the position of the rear end of said nonmagnetic intermediate layer; a magnetization direction control multilayer arrangement is interposed at an area where the magnetization direction control area for said first ferromagnetic layer is opposite to the magnetization direction control area for said second ferromagnetic layer to produce magnetizations of the said first and second ferromagnetic layers which are antiparallel with each other; and said sensor area is provided at both width direction ends with biasing layers working such that the mutually antiparallel magnetizations of said first and second ferromagnetic layers intersect in substantially orthogonal directions.

CPP type magnetoresistive device with biasing arrangement for ferromagnetic layers having respective magnetizations orthogonal to one another, and magnetic disk system using same

A magnetoresistive device comprising a magnetoresistive unit, an upper shield layer and a lower shield layer stacked such that the magnetoresistive unit is held between them. The magnetoresistive unit comprises a nonmagnetic metal intermediate layer, a first ferromagnetic layer and a second ferromagnetic layer stacked with the nonmagnetic metal intermediate layer in the middle. When no bias magnetic field is applied, the first and second ferromagnetic layers have mutually antiparallel magnetizations. The magnetoresistive unit further comprises first and second side shield layers, and first and second biasing layers located to be magnetically coupled to the first and second side shield layers, wherein magnetic fluxes fed from the bias magnetic fields pass through the first and second side shield layers positioned in proximity to the magnetoresistive unit such that the magnetizations of the first and second ferromagnetic layers become substantially orthogonal to each other.

Magneto-resistive effect device of the CPP type, and magnetic disk system

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Tokyo, Japan

Kiyoshi Noguchi