Patents by Inventor Yusuke Tomoda

Yusuke Tomoda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20190189149
    Abstract: A magnetic recording apparatus includes a disk-shaped recording medium with a magnetic recording layer, and a recording head that magnetically writes data onto the magnetic recording layer and includes a main magnetic pole, a write shield facing the main magnetic pole and positioned with a writing gap disposed between the main magnetic pole and the write shield, and a magnetic flux control layer disposed inside the write gap between the main magnetic pole and the writing shield. The magnetic flux control layer includes a first layer including a first metal and contacting one of the main magnetic pole and the writing shield, a second control layer, and a third layer including a second metal and contacting the other one of the main magnetic pole and the writing shield. The second control layer includes a magnetic metal and contacts the first layer and the third layer.
    Type: Application
    Filed: August 27, 2018
    Publication date: June 20, 2019
    Inventors: Masaya OHTAKE, Akihiko TAKEO, Gaku KOIZUMI, Yusuke TOMODA
  • Patent number: 10276193
    Abstract: According to one embodiment, a magnetic head includes a magnetic pole having a first surface, a first shield separated from the magnetic pole along the first surface, and a stacked body provided between the magnetic pole and the first shield. The stacked body includes a magnetic layer, and first and second conductive layers. The magnetic layer includes at least one selected from the group consisting of Fe, Co, and Ni. The first conductive layer contacts the magnetic pole and the magnetic layer, and is provided between the magnetic pole and the magnetic layer. The second conductive layer contacts the magnetic layer and the first shield, is provided between the magnetic layer and the first shield. The first shield has a first shield surface contacting the second conductive layer. A ratio of a length of the magnetic layer to a length of the first shield surface is 0.1 or more.
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: April 30, 2019
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoyuki Narita, Tomoyuki Maeda, Masaya Ohtake, Gaku Koizumi, Yusuke Tomoda, Akihiko Takeo
  • Publication number: 20190088275
    Abstract: According to one embodiment, a magnetic head includes a magnetic pole having a first surface, a first shield separated from the magnetic pole along the first surface, and a stacked body provided between the magnetic pole and the first shield. The stacked body includes a magnetic layer, and first and second conductive layers. The magnetic layer includes at least one selected from the group consisting of Fe, Co, and Ni. The first conductive layer contacts the magnetic pole and the magnetic layer, and is provided between the magnetic pole and the magnetic layer. The second conductive layer contacts the magnetic layer and the first shield, is provided between the magnetic layer and the first shield. The first shield has a first shield surface contacting the second conductive layer. A ratio of a length of the magnetic layer to a length of the first shield surface is 0.1 or more.
    Type: Application
    Filed: March 6, 2018
    Publication date: March 21, 2019
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoyuki NARITA, Tomoyuki MAEDA, Masaya OHTAKE, Gaku KOIZUMI, Yusuke TOMODA, Akihiko TAKEO
  • Publication number: 20190066717
    Abstract: A magnetic head includes a main magnetic pole, a write shield separated from the main magnetic pole by a write gap, a first side shield that is separated from the main magnetic pole by a first side gap, a second side shield that is separated from the main magnetic pole by a second side gap, a first layer that has a first magnetic relative permeability and is disposed in the write gap between the main magnetic pole and the write shield, and a second layer that has a second magnetic relative permeability and is disposed in the first side gap and the second side gap, wherein the first magnetic relative permeability is smaller than the second magnetic relative permeability.
    Type: Application
    Filed: February 22, 2018
    Publication date: February 28, 2019
    Inventors: Masaya OHTAKE, Akihiko Takeo, Naoyuki Narita, Gaku Koizumi, Yusuke Tomoda, Tomoyuki Maeda
  • Publication number: 20190051322
    Abstract: According to one embodiment, a magnetic disk device conforming to perpendicular magnetic recording includes a magnetic disk, a recording head, and a controller. The head includes a main magnetic pole, a return magnetic pole, a recording coil, and a conductive member in which end surfaces are connected to opposed surfaces of a write gap which is opposed to a distal portion of the main magnetic pole and a distal portion of the return magnetic pole, and a resistance value varies. The controller applies a current to the recording coil to excite the magnetic flux in the recording operation, and applies a current at a constant voltage to the magnetic circuit via the comductive member.
    Type: Application
    Filed: February 14, 2018
    Publication date: February 14, 2019
    Inventors: Gaku Koizumi, Akihiko Takeo, Naoyuki Narita, Masaya Ohtake, Yusuke Tomoda, Tomoyuki Maeda
  • Patent number: 10037769
    Abstract: According to one embodiment, a magnetic disk device includes a disk, a head including a main pole configured to apply a recording magnetic field to the disk, and side shields provided in a first direction with respect to the main pole and possessing a magnetic field in the magnetization direction of the first direction, and a controller configured to output a recording current in which a magnitude of a first electric current and a magnitude of a second electric current opposite to the first electric current in direction of the current are different from each other to the head according to the magnetic field of the side shields.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: July 31, 2018
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Tomoda, Koji Yano
  • Patent number: 9978404
    Abstract: According to one embodiment, a magnetic recording head includes an air bearing surface, a magnetic pole having a distal end portion, a write shield opposed to the distal end portion of the magnetic pole across a write gap, and a high-frequency oscillator between the magnetic pole and the write shield in the write gap. The high-frequency oscillator includes a spin injection layer, an intermediate layer and an oscillation layer which are stacked in a head travel direction. A film thickness of the spin injection layer in the head travel direction at a height position away from the air bearing surface is greater than a film thickness of the spin injection layer in the head travel direction on the air bearing surface.
    Type: Grant
    Filed: July 13, 2015
    Date of Patent: May 22, 2018
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Taguchi, Yusuke Tomoda, Kenichiro Yamada, Satoshi Shirotori, Naoyuki Narita
  • Publication number: 20160314809
    Abstract: According to one embodiment, a magnetic recording head includes an air bearing surface, a magnetic pole having a distal end portion, a write shield opposed to the distal end portion of the magnetic pole across a write gap, and a high-frequency oscillator between the magnetic pole and the write shield in the write gap. The high-frequency oscillator includes a spin injection layer, an intermediate layer and an oscillation layer which are stacked in a head travel direction. A film thickness of the spin injection layer in the head travel direction at a height position away from the air bearing surface is greater than a film thickness of the spin injection layer in the head travel direction on the air bearing surface.
    Type: Application
    Filed: July 13, 2015
    Publication date: October 27, 2016
    Inventors: Tomoko Taguchi, Yusuke Tomoda, Kenichiro Yamada, Satoshi Shirotori, Naoyuki Narita
  • Publication number: 20160225392
    Abstract: According to one embodiment, a recording head includes a recoding magnetic pole which applies a recording magnetic field, a write shield which faces the recording magnetic pole across a recording gap, and a spin-torque oscillator provided in the recording gap between the recording magnetic pole and the write shield. The spin-torque oscillator is physically and/or magnetically destroyed and has resistance greater than or equal to a predetermined value.
    Type: Application
    Filed: March 3, 2016
    Publication date: August 4, 2016
    Inventors: Akihiko Takeo, Tomomi Funayama, Yusuke Tomoda
  • Publication number: 20160163340
    Abstract: According to one embodiment, a microwave-assisted magnetic head includes a main magnetic pole configured to apply a recording magnetic field to a magnetic recording medium, an auxiliary magnetic pole configured to constitute a magnetic circuit together with the main magnetic pole, and a domain propagation element including a domain propagation path having two ends and a magnetic anisotropy perpendicular to a domain propagation direction, and a domain input portion configured to write a magnetic domain in the domain propagation path, and a current supply mechanism connected to the domain propagation path, and at least part of the domain propagation path passes between the main magnetic pole and the auxiliary magnetic pole.
    Type: Application
    Filed: March 4, 2015
    Publication date: June 9, 2016
    Inventors: Naoyuki Narita, Kenichiro Yamada, Yusuke Tomoda, Akihiko Takeo
  • Patent number: 9208800
    Abstract: According to one embodiment, a recording head includes a main pole, a trailing shield including a first connecting portion and a second connecting portion, and configured to form together with the main pole a first magnetic core, a leading shield including a first connecting portion connected to the main pole through a magnetic material and an end portion opposing to the end portion of the main pole through a non-magnetic material, and configured to form together with the main pole a second magnetic core, and first and second coils wound around the first and second magnetic cores, and a connection terminal configured to flow a current through the main pole, non-magnetic conductive layer, and trailing shield.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: December 8, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Taguchi, Yusuke Tomoda
  • Publication number: 20140334030
    Abstract: According to one embodiment, a recording head includes a main pole, a trailing shield including a first connecting portion and a second connecting portion, and configured to form together with the main pole a first magnetic core, a leading shield including a first connecting portion connected to the main pole through a magnetic material and an end portion opposing to the end portion of the main pole through a non-magnetic material, and configured to form together with the main pole a second magnetic core, and first and second coils wound around the first and second magnetic cores, and a connection terminal configured to flow a current through the main pole, non-magnetic conductive layer, and trailing shield.
    Type: Application
    Filed: July 25, 2014
    Publication date: November 13, 2014
    Inventors: Tomoko TAGUCHI, Yusuke TOMODA
  • Patent number: 8810961
    Abstract: According to one embodiment, a recording head includes a main pole, a trailing shield including a first connecting portion and a second connecting portion, and configured to form together with the main pole a first magnetic core, a leading shield including a first connecting portion connected to the main pole through a magnetic material and an end portion opposing to the end portion of the main pole through a non-magnetic material, and configured to form together with the main pole a second magnetic core, and first and second coils wound around the first and second magnetic cores, and a connection terminal configured to flow a current through the main pole, non-magnetic conductive layer, and trailing shield.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: August 19, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Taguchi, Yusuke Tomoda
  • Patent number: 8730616
    Abstract: According to one embodiment, a magnetic recording head includes a main pole, a trailing shield opposing the main pole with a write gap therebetween, and a high-frequency oscillator between a distal end portion of the main pole and the trailing shield configured to produce a high-frequency magnetic field. The high-frequency oscillator includes a lower end surface facing the recording medium and an upper end surface substantially parallel to the lower end surface. The width of the lower end surface in a track-width direction is smaller than that of the upper end surface.
    Type: Grant
    Filed: August 14, 2012
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichiro Yamada, Yusuke Tomoda, Tomoko Taguchi, Katsuhiko Koui
  • Publication number: 20140002925
    Abstract: According to one embodiment, a magnetic recording head includes a main pole configured to apply a recording magnetic field to a recording layer of a recording medium, and a high-frequency oscillator disposed adjacent to the main pole and near a air-bearing surface which faces the recording medium. The high-frequency oscillator includes a lower end surface located nearest to the air-bearing surface and an upper end surface located farthest from the air-bearing surface. A length of the lower end surface in a cross track direction is longer than a length of the upper end surface in the cross track direction.
    Type: Application
    Filed: December 12, 2012
    Publication date: January 2, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yusuke TOMODA, Kenichiro YAMADA, Naoyuki NARITA
  • Patent number: 8614861
    Abstract: According to one embodiment, a magnetic recording head includes a main pole configured to apply a recording magnetic field to a recording layer of a recording medium, and a high-frequency oscillator disposed adjacent to the main pole and near a air-bearing surface which faces the recording medium. The high-frequency oscillator includes a lower end surface located nearest to the air-bearing surface and an upper end surface located farthest from the air-bearing surface. A length of the lower end surface in a cross track direction is longer than a length of the upper end surface in the cross track direction.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: December 24, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Tomoda, Kenichiro Yamada, Naoyuki Narita
  • Patent number: 8605391
    Abstract: According to one embodiment, a magnetic head has a main magnetic pole, a write-shield constituting the main magnetic pole and a magnetic circuit, and a spin torque oscillation element provided between the main magnetic pole and the write-shield. The spin torque oscillation element is provided with a first oscillation layer, a nonmagnetic spin sink layer, a second oscillation layer, a nonmagnetic intermediate layer, and a spin injection layer provided in sequence from the write-shield side to the main magnetic pole side. The nonmagnetic spin sink layer is formed of at least one element selected from the group consisting of Ru, Rh, Ta, W, Cr, Ir, Mo, Re, Nb, Pt, and Pd.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: December 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Koui, Shuichi Murakami, Mariko Kitazaki, Yusuke Tomoda, Norihito Fujita
  • Patent number: 8564904
    Abstract: According to one embodiment, a magnetic head includes a reproducing section. The reproducing section detects a medium magnetic field recorded in a magnetic recording medium. The reproducing section includes a stacked film and a magnetic field application unit. The stacked film includes a first magnetization layer and a second magnetization layer. The first magnetization layer has a perpendicular magnetic anisotropy. A magnetization of the first magnetization layer being is fixed. The second magnetization layer is stacked with the first magnetization layer and oscillates. The magnetic field application unit is stacked with the stacked film and applies a bias magnetic field having a component along the first axis to the stacked film. A resistance of the stacked film changes in accordance with the medium magnetic field when a current not less than a value at which the second magnetization layer oscillates is passed.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: October 22, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Masayuki Takagishi, Kenichiro Yamada, Susumu Hashimoto, Yusuke Tomoda
  • Publication number: 20130250456
    Abstract: According to one embodiment, a magnetic recording head includes a main pole, a trailing shield opposing the main pole with a write gap therebetween, and a high-frequency oscillator between a distal end portion of the main pole and the trailing shield configured to produce a high-frequency magnetic field. The high-frequency oscillator includes a lower end surface facing the recording medium and an upper end surface substantially parallel to the lower end surface. The width of the lower end surface in a track-width direction is smaller than that of the upper end surface.
    Type: Application
    Filed: August 14, 2012
    Publication date: September 26, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kenichiro YAMADA, Yusuke TOMODA, Tomoko TAGUCHI, Katsuhiko KOUI
  • Publication number: 20130063840
    Abstract: According to one embodiment, a magnetic head has a main magnetic pole, a write-shield constituting the main magnetic pole and a magnetic circuit, and a spin torque oscillation element provided between the main magnetic pole and the write-shield. The spin torque oscillation element is provided with a first oscillation layer, a nonmagnetic spin sink layer, a second oscillation layer, a nonmagnetic intermediate layer, and a spin injection layer provided in sequence from the write-shield side to the main magnetic pole side. The nonmagnetic spin sink layer is formed of at least one element selected from the group consisting of Ru, Rh, Ta, W, Cr, Ir, Mo, Re, Nb, Pt, and Pd.
    Type: Application
    Filed: June 22, 2012
    Publication date: March 14, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Katsuhiko Koui, Shuichi Murakami, Mariko Kitazaki, Yusuke Tomoda, Norihito Fujita