Patents by Inventor Akio Fukushima

Akio Fukushima 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: 20220222564
    Abstract: The present invention addresses the problem of providing a quantum bit cell and a quantum bit integrated circuit having an easy-to-integrate structure. The quantum bit cell of the present invention including a spin torque oscillator capable of emitting a microwave with a propagation distance of 1 ?m or less and having a maximum diameter of 1 ?m or less, and a solid-state element quantum bit arranged near the spin torque oscillator at an interval of the propagation distance or less, where a quantum two-level system is controlled by the microwave.
    Type: Application
    Filed: April 14, 2020
    Publication date: July 14, 2022
    Inventors: Hitoshi Kubota, Shingo Tamaru, Akio Fukushima, Takahiro Mori, Takashi Matsukawa
  • Patent number: 10432144
    Abstract: A high-frequency phase-locked oscillation circuit having an extremely narrow peak width and a stable frequency so that a high-frequency wave that is oscillated by the MR element solves a problem of a large peak width of oscillation spectrum. The high-frequency phase-locked oscillation circuit includes a magnetoresistive element that oscillates a high-frequency wave with an oscillating frequency; a reference signal source that outputs a reference signal with a reference frequency; a phase-locked loop circuit having a phase comparator, a loop filter, and a frequency divider; an adder that adds a phase error signal output from the loop filter and a bias voltage for oscillating the high-frequency wave from the magnetoresistive element, and that inputs an added bias voltage to the magnetoresistive element; and a filter provided between the frequency divider and the magnetoresistive element.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: October 1, 2019
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Shingo Tamaru, Hitoshi Kubota, Akio Fukushima, Shinji Yuasa
  • Publication number: 20180302035
    Abstract: The present invention provides a high-frequency phase-locked oscillation circuit having an extremely narrow peak width and a stable frequency so that a high-frequency wave that is oscillated by the MR element solves a problem of a large peak width of oscillation spectrum.
    Type: Application
    Filed: April 27, 2016
    Publication date: October 18, 2018
    Inventors: Shingo Tamaru, Hitoshi Kubota, Akio Fukushima, Shinji Yuasa
  • Patent number: 9620189
    Abstract: A magnetic memory according to an embodiment includes at least one MTJ element, the MTJ element including: a magnetic multilayer structure including a first magnetic layer in which a direction of magnetization is fixed, a second magnetic layer in which a direction of magnetization is changeable, and a tunnel barrier layer located between the first and second magnetic layers; a first electrode provided on a first surface of the magnetic multilayer structure; a second electrode provided on a second surface of the magnetic multilayer structure; an insulating film provided on a side surface of the magnetic multilayer structure; and a control electrode provided on the side surface of the magnetic multilayer structure with the insulating film located therebetween, a voltage being applied to the control electrode in a read operation, which increases an energy barrier for changing the magnetization of the second magnetic layer.
    Type: Grant
    Filed: November 20, 2015
    Date of Patent: April 11, 2017
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoharu Shimomura, Eiji Kitagawa, Minoru Amano, Daisuke Saida, Kay Yakushiji, Takayuki Nozaki, Shinji Yuasa, Akio Fukushima, Hiroshi Imamura, Hitoshi Kubota
  • Patent number: 9437810
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer having a variable magnetization direction; a second magnetic layer having an invariable magnetization direction; and a tunnel barrier layer provided between the first magnetic layer and the second magnetic layer and including an MgFeO film, wherein the MgFeO film contains at least one element selected from a group consisting of Ti, V, Mn, and Cu.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: September 6, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Eiji Kitagawa, Takao Ochiai, Kay Yakushiji, Makoto Konoto, Hitoshi Kubota, Shinji Yuasa, Takayuki Nozaki, Akio Fukushima
  • Publication number: 20160118098
    Abstract: A magnetic memory according to an embodiment includes at least one MTJ element, the MTJ element including: a magnetic multilayer structure including a first magnetic layer in which a direction of magnetization is fixed, a second magnetic layer in which a direction of magnetization is changeable, and a tunnel barrier layer located between the first and second magnetic layers; a first electrode provided on a first surface of the magnetic multilayer structure; a second electrode provided on a second surface of the magnetic multilayer structure; an insulating film provided on a side surface of the magnetic multilayer structure; and a control electrode provided on the side surface of the magnetic multilayer structure with the insulating film located therebetween, a voltage being applied to the control electrode in a read operation, which increases an energy barrier for changing the magnetization of the second magnetic layer.
    Type: Application
    Filed: November 20, 2015
    Publication date: April 28, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoharu SHIMOMURA, Eiji KITAGAWA, Minoru AMANO, Daisuke SAIDA, Kay YAKUSHIJI, Takayuki NOZAKI, Shinji YUASA, Akio FUKUSHIMA, Hiroshi IMAMURA, Hitoshi KUBOTA
  • Patent number: 9230628
    Abstract: A magnetic memory according to an embodiment includes at least one MTJ element, the MTJ element including: a magnetic multilayer structure including a first magnetic layer in which a direction of magnetization is fixed, a second magnetic layer in which a direction of magnetization is changeable, and a tunnel barrier layer located between the first and second magnetic layers; a first electrode provided on a first surface of the magnetic multilayer structure; a second electrode provided on a second surface of the magnetic multilayer structure; an insulating film provided on a side surface of the magnetic multilayer structure; and a control electrode provided on the side surface of the magnetic multilayer structure with the insulating film located therebetween, a voltage being applied to the control electrode in a read operation, which increases an energy barrier for changing the magnetization of the second magnetic layer.
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: January 5, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoharu Shimomura, Eiji Kitagawa, Minoru Amano, Daisuke Saida, Kay Yakushiji, Takayuki Nozaki, Shinji Yuasa, Akio Fukushima, Hiroshi Imamura, Hitoshi Kubota
  • Patent number: 9219227
    Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer, and including a first magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the first magnetic film including MnxGa100-x (45?x<64 atomic %); a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer, and including a second magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the second magnetic film including MnyGa100-y (45?y<64 atomic %). The first and second magnetic layers include different Mn composition rates from each other, a magnetization direction of the first magnetic layer is changeable by a current flowing between the first magnetic layer and the second magnetic layer via the first nonmagnetic layer.
    Type: Grant
    Filed: November 20, 2014
    Date of Patent: December 22, 2015
    Assignees: KABUSHIKI KAISHA TOSHIBA, WPI-AIMR, Tohoku University
    Inventors: Tadaomi Daibou, Junichi Ito, Tadashi Kai, Minoru Amano, Hiroaki Yoda, Terunobu Miyazaki, Shigemi Mizukami, Koji Ando, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Akio Fukushima, Taro Nagahama, Takahide Kubota
  • Patent number: 9182304
    Abstract: A power meter includes a first measurement unit 7 that measures a force applied to a first pedal B322 and calculates predetermined first information (power and/or torque) on the first pedal B322, and a second measurement unit 6 that measures a force applied to a second pedal B321 and calculates second information (power and/or torque) on the second pedal B321, which is the same kind of the first information. The first measurement unit 7 transmits first information data indicating the first information to the second measurement unit 6, and the second measurement unit 6 adds the first information to the second measurement information and transmits an added value data indicating an added value obtained by adding the first information to the second information.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: November 10, 2015
    Assignee: PIONEER CORPORATION
    Inventors: Tsuyoshi Namiki, Ryujiro Fujita, Takehiko Shioda, Akio Fukushima, Yasuteru Kodama, Ryushin Kametani
  • Patent number: 9087980
    Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer, and including a first magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the first magnetic film including MnxGa100-x (45?x<64 atomic %); a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer, and including a second magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the second magnetic film including MnyGa100-y (45?y<64 atomic %). The first and second magnetic layers include different Mn composition rates from each other, a magnetization direction of the first magnetic layer is changeable by a current flowing between the first magnetic layer and the second magnetic layer via the first nonmagnetic layer.
    Type: Grant
    Filed: February 18, 2014
    Date of Patent: July 21, 2015
    Assignees: KABUSHIKI KAISHA TOSHIBA, WPI-AIMR, Tohoku University
    Inventors: Tadaomi Daibou, Junichi Ito, Tadashi Kai, Minoru Amano, Hiroaki Yoda, Terunobu Miyazaki, Shigemi Mizukami, Koji Ando, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Akio Fukushima, Taro Nagahama, Takahide Kubota
  • Publication number: 20150076635
    Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer, and including a first magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the first magnetic film including MnxGa100-x (45?x<64 atomic %); a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer, and including a second magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the second magnetic film including MnyGa100-y (45?y<64 atomic %). The first and second magnetic layers include different Mn composition rates from each other, a magnetization direction of the first magnetic layer is changeable by a current flowing between the first magnetic layer and the second magnetic layer via the first nonmagnetic layer.
    Type: Application
    Filed: November 20, 2014
    Publication date: March 19, 2015
    Applicants: KABUSHIKI KAISHA TOSHIBA, WPI-AIMR, Tohoku University
    Inventors: Tadaomi DAIBOU, Junichi ITO, Tadashi KAI, Minoru AMANO, Hiroaki YODA, Terunobu MIYAZAKI, Shigemi MIZUKAMI, Koji ANDO, Kay YAKUSHIJI, Shinji YUASA, Hitoshi KUBOTA, Akio FUKUSHIMA, Taro NAGAHAMA, Takahide KUBOTA
  • Publication number: 20140283622
    Abstract: There are provided a versatile power meter, a power measurement method, a program and a recording medium. The power meter includes a first measurement unit 7 that measures a force applied to a first pedal B322 and calculates predetermined first information (power and/or torque) on the first pedal B322, and a second measurement unit 6 that measures a force applied to a second pedal B321 and calculate second information (power and/or torque) on the second pedal B321, which is the same kind of the first information. The first measurement unit 7 transmits first information data indicating the first information to the second measurement unit 6, and the second measurement unit 6 adds the first information to the second measurement information and transmits an added value data indicating an added vale obtained by adding the first information to the second information.
    Type: Application
    Filed: September 30, 2011
    Publication date: September 25, 2014
    Applicant: PIONEER CORPORATION
    Inventors: Tsuyoshi Namiki, Ryujiro Fujita, Takehiko Shioda, Akio Fukushima, Yasuteru Kodama, Ryushin Kametani
  • Publication number: 20140269038
    Abstract: A magnetic memory according to an embodiment includes at least one MTJ element, the MTJ element including: a magnetic multilayer structure including a first magnetic layer in which a direction of magnetization is fixed, a second magnetic layer in which a direction of magnetization is changeable, and a tunnel barrier layer located between the first and second magnetic layers; a first electrode provided on a first surface of the magnetic multilayer structure; a second electrode provided on a second surface of the magnetic multilayer structure; an insulating film provided on a side surface of the magnetic multilayer structure; and a control electrode provided on the side surface of the magnetic multilayer structure with the insulating film located therebetween, a voltage being applied to the control electrode in a read operation, which increases an energy barrier for changing the magnetization of the second magnetic layer.
    Type: Application
    Filed: March 6, 2014
    Publication date: September 18, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoharu SHIMOMURA, Eiji KITAGAWA, Minoru AMANO, Daisuke SAIDA, Kay YAKUSHIJI, Takayuki NOZAKI, Shinji YUASA, Akio FUKUSHIMA, Hiroshi IMAMURA, Hitoshi KUBOTA
  • Publication number: 20140264673
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer having a variable magnetization direction; a second magnetic layer having an invariable magnetization direction; and a tunnel barrier layer provided between the first magnetic layer and the second magnetic layer and including an MgFeO film, wherein the MgFeO film contains at least one element selected from a group consisting of Ti, V, Mn, and Cu.
    Type: Application
    Filed: February 28, 2014
    Publication date: September 18, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Eiji Kitagawa, Takao Ochiai, Kay Yakushiji, Makoto Konoto, Hitoshi Kubota, Shinji Yuasa, Takayuki Nozaki, Akio Fukushima
  • Publication number: 20140159177
    Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer, and including a first magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the first magnetic film including MnxGa100-x (45?x<64 atomic %); a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer, and including a second magnetic film having an axis of easy magnetization In a direction perpendicular to a film plane, the second magnetic film including MnyGa100-y (45?y<64 atomic %). The first and second magnetic layers include different Mn composition rates from each other, a magnetization direction of the first magnetic layer is changeable by a current flowing between the first magnetic layer and the second magnetic layer via the first nonmagnetic layer.
    Type: Application
    Filed: February 18, 2014
    Publication date: June 12, 2014
    Applicants: WPI-AIMR, Tohoku University, Kabushiki Kaisha Toshiba
    Inventors: Tadaomi DAIBOU, Junichi Ito, Tadashi Kai, Minoru Amano, Hiroaki Yoda, Terunobu Miyazaki, Shigemi Mizukami, Koji Ando, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Akio Fukushima, Taro Nagahama, Takahide Kubota
  • Patent number: 8705269
    Abstract: A magnetoresistive element according to an embodiment includes: a first and second magnetic layers having an easy axis of magnetization in a direction perpendicular to a film plane; and a first nonmagnetic layer interposed between the first and second magnetic layers, at least one of the first and second magnetic layers including a structure formed by stacking a first and second magnetic films, the second magnetic film being located closer to the first nonmagnetic layer, the second magnetic film including a structure formed by repeating stacking of a magnetic material layer and a nonmagnetic material layer at least twice, the nonmagnetic material layers of the second magnetic film containing at least one element selected from the group consisting of Ta, W, Hf, Zr, Nb, Mo, Ti, V, and Cr, one of the first and second magnetic layers having a magnetization direction that is changed by applying a current.
    Type: Grant
    Filed: September 14, 2011
    Date of Patent: April 22, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshihiko Nagase, Tadashi Kai, Makoto Nagamine, Katsuya Nishiyama, Eiji Kitagawa, Tadaomi Daibou, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando
  • Patent number: 8680632
    Abstract: A magnetoresistive element according to an embodiment includes: a base layer; a first magnetic layer formed on the base layer, and including a first magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the first magnetic film including MnxGa100-x (45?x<64 atomic %); a first nonmagnetic layer formed on the first magnetic layer; and a second magnetic layer formed on the first nonmagnetic layer, and including a second magnetic film having an axis of easy magnetization in a direction perpendicular to a film plane, the second magnetic film including MnyGa100-y (45?y<64 atomic %). The first and second magnetic layers include different Mn composition rates from each other, a magnetization direction of the first magnetic layer is changeable by a current flowing between the first magnetic layer and the second magnetic layer via the first nonmagnetic layer.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: March 25, 2014
    Assignees: Kabushiki Kaisha Toshiba, WPI-AIMR, Tohoku University
    Inventors: Tadaomi Daibou, Junichi Ito, Tadashi Kai, Minoru Amano, Hiroaki Yoda, Terunobu Miyazaki, Shigemi Mizukami, Koji Ando, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Akio Fukushima, Taro Nagahama, Takahide Kubota
  • Publication number: 20130288397
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including perpendicular anisotropy to a film surface and an invariable magnetization direction, the first magnetic layer having a magnetic film including an element selected from a first group including Tb, Gd, and Dy and an element selected from a second group including Co and Fe, a second magnetic layer including perpendicular magnetic anisotropy to the film surface and a variable magnetization direction, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer. The magnetic film includes amorphous phases and crystals whose particle sizes are 0.5 nm or more.
    Type: Application
    Filed: July 1, 2013
    Publication date: October 31, 2013
    Inventors: Eiji Kitagawa, Tadaomi Daibou, Yutaka Hashimoto, Masaru Tokou, Tadashi Kai, Makato Nagamine, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando
  • Patent number: 8521795
    Abstract: A random number generating device is constructed such that it has improved random number generation rate and allows for construction of compact circuit with ease. The random number generating device includes a magnetoresistive element that has three layers consisting of a magnetization free layer, an interlayer, and a magnetization fixed layer, and has at least two resistance values depending on arrangement of magnetization in the magnetization free layer and the magnetization fixed layer, wherein the magnetoresistive element is subjected to be applied with a magnetization current so that the inversion probability of the magnetization free layer assumes a value between 0 and 1, through which the resistance value of the magnetoresistive element is extracted as random numbers.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: August 27, 2013
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Akio Fukushima, Hitoshi Kubota, Kay Yakushiji, Shinji Yuasa, Koji Ando
  • Patent number: 8502331
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including perpendicular anisotropy to a film surface and an invariable magnetization direction, the first magnetic layer having a magnetic film including an element selected from a first group including Tb, Gd, and Dy and an element selected from a second group including Co and Fe, a second magnetic layer including perpendicular magnetic anisotropy to the film surface and a variable magnetization direction, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer. The magnetic film includes amorphous phases and crystals whose particle sizes are 0.5 nm or more.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: August 6, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Tadaomi Daibou, Yutaka Hashimoto, Masaru Tokou, Tadashi Kai, Makoto Nagamine, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando