Patents by Inventor Alan Kalitsov

Alan Kalitsov 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).

  • Patent number: 11887640
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Grant
    Filed: June 7, 2021
    Date of Patent: January 30, 2024
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Derek Stewart, Alan Kalitsov, Bhagwati Prasad
  • Patent number: 11889702
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Grant
    Filed: June 7, 2021
    Date of Patent: January 30, 2024
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Alan Kalitsov, Derek Stewart, Bhagwati Prasad
  • Patent number: 11871679
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Grant
    Filed: June 7, 2021
    Date of Patent: January 9, 2024
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Alan Kalitsov, Derek Stewart, Bhagwati Prasad
  • Patent number: 11839162
    Abstract: Magnetoelectric or magnetoresistive memory cells may include a plurality of reference layers and optionally a plurality of free layers to enhance the tunneling magnetoresistance (TMR) ratio.
    Type: Grant
    Filed: June 25, 2021
    Date of Patent: December 5, 2023
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Alan Kalitsov, Derek Stewart, Bhagwati Prasad, Goran Mihajlovic
  • Publication number: 20230307029
    Abstract: A magnetoresistive memory cell includes a first terminal electrode, a second terminal electrode, and a magnetoresistive layer stack located between the first terminal electrode and the second terminal electrode and including, from one side to another, a reference layer, a dielectric tunnel barrier layer, a free layer, and a material layer having two different states of lattice deformation which have different average in-plane lattice constants and which are configured to apply different in-plane stress. The material layer may be a metal-insulator transition (MIT) material layer that exhibits a phase transition between an insulator state and a metal state.
    Type: Application
    Filed: October 20, 2022
    Publication date: September 28, 2023
    Inventors: Alan KALITSOV, Derek STEWART, Bhagwati PRASAD
  • Publication number: 20230307028
    Abstract: A magnetoresistive memory cell includes a magnetoresistive layer stack containing a reference layer, a nonmagnetic spacer layer, and a free layer. A ferroelectric material layer having two stable ferroelectric states is coupled to a strain-modulated ferromagnetic layer to alter a sign of magnetic exchange coupling between the strain-modulated ferromagnetic layer and the free layer. The strain-modulated ferromagnetic layer may be the reference layer or a perpendicular magnetic anisotropy layer that is located proximate to the ferroelectric material layer. The magnetoresistive memory cell may be configured as a three-terminal device or as a two-terminal device, and may be configured as a tunneling magnetoresistance (TMR) device or as a giant magnetoresistance (GMR) device.
    Type: Application
    Filed: March 24, 2022
    Publication date: September 28, 2023
    Inventors: Alan KALITSOV, Derek STEWART, Ananth KAUSHIK, Gerardo BERTERO
  • Publication number: 20230307027
    Abstract: A magnetoresistive memory cell includes a magnetoresistive layer stack containing a reference layer, a nonmagnetic spacer layer, and a free layer. A ferroelectric material layer having two stable ferroelectric states is coupled to a strain-modulated ferromagnetic layer to alter a sign of magnetic exchange coupling between the strain-modulated ferromagnetic layer and the free layer. The strain-modulated ferromagnetic layer may be the reference layer or a perpendicular magnetic anisotropy layer that is located proximate to the ferroelectric material layer. The magnetoresistive memory cell may be configured as a three-terminal device or as a two-terminal device, and may be configured as a tunneling magnetoresistance (TMR) device or as a giant magnetoresistance (GMR) device.
    Type: Application
    Filed: March 24, 2022
    Publication date: September 28, 2023
    Inventors: Alan KALITSOV, Derek STEWART, Ananth KAUSHIK, Gerardo BERTERO
  • Publication number: 20230107190
    Abstract: A magnetic tunnel junction may include a platinum-containing layer including at least one of Ir, Hf or Ru in contact with a free layer, or a combination of a platinum layer and a Hf or Ir layer formed on opposite sides of a free layer.
    Type: Application
    Filed: December 13, 2022
    Publication date: April 6, 2023
    Inventors: Alan KALITSOV, Bhagwati PRASAD, Rajesh CHOPDEKAR, Lei WAN, Tiffany SANTOS
  • Publication number: 20220393100
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Application
    Filed: June 7, 2021
    Publication date: December 8, 2022
    Inventors: Alan KALITSOV, Derek STEWART, Bhagwati PRASAD
  • Publication number: 20220392505
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Application
    Filed: June 7, 2021
    Publication date: December 8, 2022
    Inventors: Derek STEWART, Alan KALITSOV, Bhagwati PRASAD
  • Publication number: 20220392953
    Abstract: A magnetoelectric memory device includes a magnetic tunnel junction located between a first electrode and a second electrode. The magnetic tunnel junction includes a reference layer, a nonmagnetic tunnel barrier layer, a free layer, and a dielectric capping layer. At least one layer that provides voltage-controlled magnetic anisotropy is provided within the magnetic tunnel junction, which may include a pair of nonmagnetic metal dust layers located on, or within, the free layer, or a two-dimensional metal compound layer including a compound of a nonmagnetic metallic element and a nonmetallic element.
    Type: Application
    Filed: June 7, 2021
    Publication date: December 8, 2022
    Inventors: Alan KALITSOV, Derek STEWART, Bhagwati PRASAD
  • Patent number: 11417379
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Grant
    Filed: October 27, 2020
    Date of Patent: August 16, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Alan Kalitsov, Bhagwati Prasad, Derek Stewart
  • Patent number: 11411170
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Grant
    Filed: October 27, 2020
    Date of Patent: August 9, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Alan Kalitsov, Bhagwati Prasad, Derek Stewart
  • Patent number: 11349066
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Grant
    Filed: October 27, 2020
    Date of Patent: May 31, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Alan Kalitsov, Bhagwati Prasad, Derek Stewart
  • Publication number: 20220130442
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Application
    Filed: October 27, 2020
    Publication date: April 28, 2022
    Inventors: Alan KALITSOV, Bhagwati PRASAD, Derek STEWART
  • Publication number: 20220131068
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Application
    Filed: October 27, 2020
    Publication date: April 28, 2022
    Inventors: Alan KALITSOV, Bhagwati PRASAD, Derek STEWART
  • Publication number: 20220131067
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction including a free layer, at least two tunneling dielectric barrier layers, and at least one metallic quantum well layer. The quantum well layer leads to the resonant electron tunneling through the magnetic tunnel junction in such a way that it strongly enhances the tunneling probability for one of the magnetization states of the free layer, while this tunneling probability remains much smaller in the opposite magnetization state of the free layer. The device can be configured in a spin transfer torque device configuration, a voltage-controlled magnetic anisotropy, a voltage controlled exchange coupling device configuration, or a spin-orbit-torque device configuration.
    Type: Application
    Filed: October 27, 2020
    Publication date: April 28, 2022
    Inventors: Alan KALITSOV, Bhagwati PRASAD, Derek STEWART
  • Patent number: 11276446
    Abstract: A magnetic memory device includes a first electrode, a second electrode, and a layer stack located between the first electrode and the second electrode. The layer stack includes a reference layer, a tunnel barrier layer, a free layer, and a magnetoelectric multiferroic layer including at least one crystalline grain. The magnetization of the magnetoelectric multiferroic layer may be axial, canted, or in-plane. For axial or canted magnetization of the magnetoelectric multiferroic layer, a deterministic switching of the free layer may be achieved through coupling with the axial component of magnetization of the magnetoelectric multiferroic layer. Alternatively, the in-plane magnetization of the magnetoelectric multiferroic layer may be employed to induce precession of the magnetization angle of the free layer.
    Type: Grant
    Filed: August 27, 2020
    Date of Patent: March 15, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov, Neil Smith
  • Patent number: 11271009
    Abstract: A ferroelectric memory device contains a two-dimensional semiconductor material layer having a band gap of at least 1.1 eV and at least one of a thickness of 1 to 5 monolayers of atoms of the semiconductor material or includes a two-dimensional charge carrier gas layer, a source contact contacting a first portion of the two-dimensional semiconductor material layer, a drain contact contacting a second portion of the two-dimensional semiconductor material layer, a ferroelectric memory element located between the source and drain contacts and adjacent to a first surface of the two-dimensional semiconductor material layer, and a conductive gate electrode located adjacent to the ferroelectric memory element.
    Type: Grant
    Filed: May 28, 2020
    Date of Patent: March 8, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Alan Kalitsov, Derek Stewart, Daniel Bedau, Gerardo Bertero
  • Publication number: 20220069200
    Abstract: A magnetic memory device includes a first electrode, a second electrode, and a layer stack located between the first electrode and the second electrode. The layer stack includes a reference layer, a tunnel barrier layer, a free layer, and a magnetoelectric multiferroic layer including at least one crystalline grain. The magnetization of the magnetoelectric multiferroic layer may be axial, canted, or in-plane. For axial or canted magnetization of the magnetoelectric multiferroic layer, a deterministic switching of the free layer may be achieved through coupling with the axial component of magnetization of the magnetoelectric multiferroic layer. Alternatively, the in-plane magnetization of the magnetoelectric multiferroic layer may be employed to induce precession of the magnetization angle of the free layer.
    Type: Application
    Filed: August 27, 2020
    Publication date: March 3, 2022
    Inventors: Bhagwati PRASAD, Alan KALITSOV, Neil SMITH