Patents by Inventor Tazumi Nagasawa

Tazumi Nagasawa 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: 20240233760
    Abstract: According to one embodiment, a magnetic sensor includes first to fourth shields, a first magnetic layer, first and second conductive layers, and first and second intermediate layer. The first magnetic layer is between the third shield and the fourth shield. The first magnetic layer includes a first face and a second face. The first face is between the first shield and the second face. The first conductive layer is provided between the third shield and the first magnetic layer. The second conductive layer is provided between the first magnetic layer and the fourth shield. The first intermediate layer is provided between the first shield and the first magnetic layer. The first intermediate layer includes a first intermediate layer face facing the first face. An area of the first intermediate layer face is smaller than an area of the first face.
    Type: Application
    Filed: July 27, 2023
    Publication date: July 11, 2024
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tazumi NAGASAWA, Satoshi SHIROTORI, Akira KIKITSU, Yoshihiro HIGASHI
  • Publication number: 20240233755
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, a conductive part, an element part, and first to fourth terminals. The conductive part is electrically insulated from the first and second magnetic poles. The first and second terminals are electrically connected to the conductive part. The element part is provided between the first and second magnetic poles and electrically connected to the first and second magnetic poles. The element part is conductive. The third terminal is electrically connected to the first magnetic pole. The fourth terminal is electrically connected to the second magnetic pole. A first magnetic pole temperature in a first state is higher than a second magnetic pole temperature of the second magnetic pole in the first state. A first current is supplied between the first and second terminals in the first state.
    Type: Application
    Filed: July 25, 2023
    Publication date: July 11, 2024
    Inventors: Yuji NAKAGAWA, Naoyuki NARITA, Tomoyuki MAEDA, Masayuki TAKAGISHI, Tazumi NAGASAWA, Ryo OSAMURA, Kosuke KURIHARA
  • Publication number: 20240233754
    Abstract: According to one embodiment, a magnetic sensor includes first to sixth shields, first and second magnetic layers, a first member, and first to fourth terminals. The first magnetic layer is provided between the first shield and the second shield. The first magnetic layer is between the third shield and the fourth shield in the second direction. The second magnetic layer is provided between the first magnetic layer and the second shield. The second magnetic layer is between the fifth shield and the sixth shield in the second direction. The second magnetic layer is electrically connected to the fifth shield and the sixth shield. The first member includes a first region and a second region. The first region is provided between the third shield and the first magnetic layer. The second region is provided between the first magnetic layer and the fourth shield.
    Type: Application
    Filed: July 27, 2023
    Publication date: July 11, 2024
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tazumi NAGASAWA, Satoshi SHIROTORI, Akira KIKITSU, Yoshihiro HIGASHI
  • Patent number: 12033676
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the second magnetic pole and the first magnetic layer, a third magnetic layer provided between the second magnetic pole and the second magnetic layer, a fourth magnetic layer provided between the second magnetic pole and the third magnetic layer, a first non-magnetic layer provided between the first magnetic layer and the first magnetic pole, a second non-magnetic layer provided between the second and first magnetic layers, a third non-magnetic layer provided between the third and second magnetic layers, a fourth non-magnetic layer provided between the fourth magnetic layer and the third magnetic layer, and a fifth non-magnetic layer provided between the second magnetic pole and the fourth magnetic layer.
    Type: Grant
    Filed: November 1, 2022
    Date of Patent: July 9, 2024
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Tazumi Nagasawa, Hirofumi Suto
  • Publication number: 20240135961
    Abstract: According to one embodiment, a magnetic sensor includes first to sixth shields, first and second magnetic layers, a first member, and first to fourth terminals. The first magnetic layer is provided between the first shield and the second shield. The first magnetic layer is between the third shield and the fourth shield in the second direction. The second magnetic layer is provided between the first magnetic layer and the second shield. The second magnetic layer is between the fifth shield and the sixth shield in the second direction. The second magnetic layer is electrically connected to the fifth shield and the sixth shield. The first member includes a first region and a second region. The first region is provided between the third shield and the first magnetic layer. The second region is provided between the first magnetic layer and the fourth shield.
    Type: Application
    Filed: July 26, 2023
    Publication date: April 25, 2024
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tazumi NAGASAWA, Satoshi SHIROTORI, Akira KIKITSU, Yoshihiro HIGASHI
  • Publication number: 20240135967
    Abstract: According to one embodiment, a magnetic sensor includes first to fourth shields, a first magnetic layer, first and second conductive layers, and first and second intermediate layer. The first magnetic layer is between the third shield and the fourth shield. The first magnetic layer includes a first face and a second face. The first face is between the first shield and the second face. The first conductive layer is provided between the third shield and the first magnetic layer. The second conductive layer is provided between the first magnetic layer and the fourth shield. The first intermediate layer is provided between the first shield and the first magnetic layer. The first intermediate layer includes a first intermediate layer face facing the first face. An area of the first intermediate layer face is smaller than an area of the first face.
    Type: Application
    Filed: July 26, 2023
    Publication date: April 25, 2024
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tazumi NAGASAWA, Satoshi SHIROTORI, Akira KIKITSU, Yoshihiro HIGASHI
  • Publication number: 20240135962
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, a conductive part, an element part, and first to fourth terminals. The conductive part is electrically insulated from the first and second magnetic poles. The first and second terminals are electrically connected to the conductive part. The element part is provided between the first and second magnetic poles and electrically connected to the first and second magnetic poles. The element part is conductive. The third terminal is electrically connected to the first magnetic pole. The fourth terminal is electrically connected to the second magnetic pole. A first magnetic pole temperature in a first state is higher than a second magnetic pole temperature of the second magnetic pole in the first state. A first current is supplied between the first and second terminals in the first state.
    Type: Application
    Filed: July 24, 2023
    Publication date: April 25, 2024
    Inventors: Yuji NAKAGAWA, Naoyuki NARITA, Tomoyuki MAEDA, Masayuki TAKAGISHI, Tazumi NAGASAWA, Ryo OSAMURA, Kosuke KURIHARA
  • Publication number: 20240046959
    Abstract: According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body. The first magnetic pole includes a first face and a second face crossing the first face. The second face includes a first face region continuous with the first face. The second magnetic pole includes a third face and a fourth face crossing the third face, and the fourth face includes a second face region that is continuous with the third face. The first face and the third face are along the third direction. The stacked body is provided between the first face region and the second face region. The stacked body includes a first magnetic layer, and a second magnetic layer provided between the first magnetic layer and the second face region. The second magnetic layer includes a second magnetic layer face facing the second face region.
    Type: Application
    Filed: February 6, 2023
    Publication date: February 8, 2024
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji NAKAGAWA, Masayuki TAKAGISHI, Naoyuki NARITA, Tomoyuki MAEDA, Tazumi NAGASAWA, Ryo OSAMURA, Kosuke KURIHARA
  • Patent number: 11881234
    Abstract: According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes first to fourth magnetic layers, and first to fifth non-magnetic layers. The second non-magnetic layer is in contact with the second and first magnetic layers. The third non-magnetic layer is in contact with the third and second magnetic layers. The fourth non-magnetic layer is in contact with the fourth and third magnetic layers. A fourth thickness of the fourth magnetic layer along a first direction from the first magnetic pole to the second magnetic pole is not less than 0.5 times and not more than 1.6 times a first thickness of the first magnetic layer along the first direction. A second thickness of the second magnetic layer along the first direction is less than the first thickness.
    Type: Grant
    Filed: July 18, 2022
    Date of Patent: January 23, 2024
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Tazumi Nagasawa
  • Patent number: 11869540
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, a stacked body, and first to third terminals. The stacked body is provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer between the first magnetic layer and the second magnetic pole, a third magnetic layer between the second magnetic layer and the second magnetic pole, a fourth magnetic layer between the third magnetic layer and the second magnetic pole, a first nonmagnetic layer between the first magnetic pole and the first magnetic layer, a second nonmagnetic layer between the first and second magnetic layers, a third nonmagnetic layer between the second and third magnetic layers, a fourth nonmagnetic layer between the third and fourth magnetic layers and a fifth nonmagnetic layer between the fourth magnetic layer and the second magnetic pole.
    Type: Grant
    Filed: August 10, 2022
    Date of Patent: January 9, 2024
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Tazumi Nagasawa, Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Ryo Osamura
  • Patent number: 11810601
    Abstract: According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a third magnetic layer provided between the second magnetic layer and the second magnetic pole, a first non-magnetic layer provided between the first and second magnetic layers, a second non-magnetic layer provided between the second and third magnetic layers, a third non-magnetic layer provided between the first magnetic pole and the first magnetic layer, and a fourth non-magnetic layer provided between the third magnetic layer and the second magnetic pole. A first magnetic pole length is shorter than a second magnetic pole length. A first magnetic layer length is longer than a second magnetic layer length.
    Type: Grant
    Filed: January 14, 2022
    Date of Patent: November 7, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Masayuki Takagishi, Naoyuki Narita, Tazumi Nagasawa, Tomoyuki Maeda
  • Publication number: 20230335154
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a first nonmagnetic layer provided between the first and second magnetic layers, a second nonmagnetic layer provided between the second magnetic layer and the second magnetic pole, and a third nonmagnetic layer provided between the first magnetic pole and the first magnetic layer. The first magnetic layer includes a first element including at least one of Fe, Co, or Ni. The second magnetic layer includes (Fe100-xCox)100-yEy. A second element E includes at least one selected from the group consisting of Cr, V, Mn, Yi, and Sc. The first magnetic layer does not include the second element.
    Type: Application
    Filed: June 16, 2023
    Publication date: October 19, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji NAKAGAWA, Naoyuki NARITA, Tomoyuki MAEDA, Masayuki TAKAGISHI, Tazumi NAGASAWA
  • Publication number: 20230326482
    Abstract: According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, a magnetic element, and a magnetic member. The magnetic element is provided between the first and second magnetic poles, and includes a first magnetic layer. The magnetic member includes a first magnetic part. A second direction from the first magnetic part to the magnetic element crosses a first direction from the first to second magnetic pole. The first magnetic part includes a magnetic material including at least one of first to third materials. The first material includes at least one selected from the group consisting of Mn3Sn, Mn3Ge and Mn3Ga. The second material includes at least one selected from the group consisting of a cubic or tetragonal compound including Mn and Ni, a cubic alloy including ?-phase Mn, and a cubic alloy including Fe. The third material includes an antiferromagnet.
    Type: Application
    Filed: June 6, 2023
    Publication date: October 12, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji NAKAGAWA, Naoyuki NARITA, Masayuki TAKAGISHI, Tomoyuki MAEDA, Tazumi NAGASAWA, Kenichiro YAMADA, Akira KIKITSU
  • Publication number: 20230267961
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, a stacked body, and first to third terminals. The stacked body is provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer between the first magnetic layer and the second magnetic pole, a third magnetic layer between the second magnetic layer and the second magnetic pole, a fourth magnetic layer between the third magnetic layer and the second magnetic pole, a first nonmagnetic layer between the first magnetic pole and the first magnetic layer, a second nonmagnetic layer between the first and second magnetic layers, a third nonmagnetic layer between the second and third magnetic layers, a fourth nonmagnetic layer between the third and fourth magnetic layers and a fifth nonmagnetic layer between the fourth magnetic layer and the second magnetic pole.
    Type: Application
    Filed: August 10, 2022
    Publication date: August 24, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Tazumi NAGASAWA, Yuji NAKAGAWA, Naoyuki NARITA, Masayuki TAKAGISHI, Tomoyuki MAEDA, Ryo OSAMURA
  • Patent number: 11721359
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a first nonmagnetic layer provided between the first and second magnetic layers, a second nonmagnetic layer provided between the second magnetic layer and the second magnetic pole, and a third nonmagnetic layer provided between the first magnetic pole and the first magnetic layer. The first magnetic layer includes a first element including at least one of Fe, Co, or Ni. The second magnetic layer includes (Fe100-xCox)100-yEy. A second element E includes at least one selected from the group consisting of Cr, V, Mn, Yi, and Sc. The first magnetic layer does not include the second element.
    Type: Grant
    Filed: January 28, 2022
    Date of Patent: August 8, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Tazumi Nagasawa
  • Patent number: 11710501
    Abstract: A magnetic head includes a first magnetic pole, a second magnetic pole, a magnetic element, and a magnetic member. The magnetic element is provided between the first and second magnetic poles, and includes a first magnetic layer. The magnetic member includes a first magnetic part. A second direction from the first magnetic part to the magnetic element crosses a first direction from the first to second magnetic pole. The first magnetic part includes a magnetic material including at least one of first to third materials. The first material includes at least one selected from the group consisting of Mn3Sn, Mn3Ge and Mn3Ga. The second material includes at least one selected from the group consisting of a cubic or tetragonal compound including Mn and Ni, a cubic alloy including ?-phase Mn, and a cubic alloy including Fe. The third material includes an antiferromagnet.
    Type: Grant
    Filed: January 28, 2022
    Date of Patent: July 25, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Tazumi Nagasawa, Kenichiro Yamada, Akira Kikitsu
  • Patent number: 11705152
    Abstract: A magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic member, a second magnetic member provided between the first magnetic member and the second magnetic pole, a first layer provided between the first and second magnetic members, and a second layer provided between the second magnetic member and the second magnetic pole. The first magnetic member includes first magnetic regions and a first nonmagnetic region. The first nonmagnetic region is between the one of the first magnetic regions and the other one of the first magnetic regions.
    Type: Grant
    Filed: August 5, 2022
    Date of Patent: July 18, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Hitoshi Iwasaki, Naoyuki Narita, Hirofumi Suto, Masayuki Takagishi, Tazumi Nagasawa
  • Publication number: 20230178102
    Abstract: According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes first to fourth magnetic layers, and first to fifth non-magnetic layers. The second non-magnetic layer is in contact with the second and first magnetic layers. The third non-magnetic layer is in contact with the third and second magnetic layers. The fourth non-magnetic layer is in contact with the fourth and third magnetic layers. A fourth thickness of the fourth magnetic layer along a first direction from the first magnetic pole to the second magnetic pole is not less than 0.5 times and not more than 1.6 times a first thickness of the first magnetic layer along the first direction. A second thickness of the second magnetic layer along the first direction is less than the first thickness.
    Type: Application
    Filed: July 18, 2022
    Publication date: June 8, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji NAKAGAWA, Naoyuki NARITA, Masayuki TAKAGISHI, Tomoyuki MAEDA, Tazumi NAGASAWA
  • Patent number: 11631423
    Abstract: According to one embodiment, a magnetic recording device includes a magnetic head and a controller. The magnetic head includes a first magnetic pole, a magnetic element including a first magnetic layer, and a coil. The controller is electrically connected to the magnetic element and the coil. The controller is configured to supply a recording current to the coil and supply an element current to the magnetic element. The recording current includes a first period of a first polarity, a second period of a second polarity, a third period that shifts from the first to second period, and a fourth period that shifts from the second to first period. The element current includes DC and AC components. The AC component in the first period is the same as the AC component in the second period, the AC component in the third period, and the AC component in the fourth period.
    Type: Grant
    Filed: January 28, 2022
    Date of Patent: April 18, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tazumi Nagasawa, Tomoyuki Maeda
  • Patent number: 11615808
    Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the second magnetic pole and the first magnetic layer, a third magnetic layer provided between the second magnetic pole and the second magnetic layer, a first non-magnetic layer provided between the first magnetic layer and the first magnetic pole, a second non-magnetic layer provided between the second and first magnetic layers, a third non-magnetic layer provided between the third and second magnetic layers, and a fourth non-magnetic layer provided between the second magnetic pole and the third magnetic layer. A thickness of the first magnetic layer is thicker than a thickness of the second magnetic layer. A thickness of the third magnetic layer is thicker than the second layer thickness.
    Type: Grant
    Filed: August 9, 2021
    Date of Patent: March 28, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yuji Nakagawa, Naoyuki Narita, Masayuki Takagishi, Tomoyuki Maeda, Tazumi Nagasawa, Hirofumi Suto