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).

  • Publication number: 20220068337
    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
  • Patent number: 11264562
    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 1, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov, Neil Smith
  • Patent number: 11222920
    Abstract: A magnetic device includes a first electrode, a second electrode, a plurality of magnetic junctions each containing a ferromagnetic reference layer and a ferromagnetic free layer located between the first electrode and the second electrode, and a plurality of magnetoelectric multiferroic portions having different structural defect densities located between the first electrode and the second electrode. Each of the plurality of magnetoelectric multiferroic portions is magnetically coupled to the ferromagnetic free layer of a respective one of the plurality of magnetic junctions.
    Type: Grant
    Filed: February 4, 2020
    Date of Patent: January 11, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov
  • Patent number: 11200934
    Abstract: A magnetoresistive 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 may include a ferroelectric material layer and a metamagnetic tunnel junction containing a metamagnetic material layer, an insulating barrier layer, and a metallic material layer. Alternatively, the layer stack may include a multiferroic material layer, the metamagnetic material layer, the insulating barrier layer, and a reference magnetization layer.
    Type: Grant
    Filed: April 20, 2020
    Date of Patent: December 14, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov
  • Patent number: 11177284
    Abstract: A ferroelectric memory device includes a two-dimensional electron gas channel, a gate electrode, and a ferroelectric element located between the gate electrode and the two-dimensional electron gas channel.
    Type: Grant
    Filed: February 24, 2020
    Date of Patent: November 16, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Peter Rabkin, Masaaki Higashitani, Alan Kalitsov
  • Publication number: 20210327483
    Abstract: A magnetoresistive 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 may include a ferroelectric material layer and a metamagnetic tunnel junction containing a metamagnetic material layer, an insulating barrier layer, and a metallic material layer. Alternatively, the layer stack may include a multiferroic material layer, the metamagnetic material layer, the insulating barrier layer, and a reference magnetization layer.
    Type: Application
    Filed: April 20, 2020
    Publication date: October 21, 2021
    Inventors: Bhagwati PRASAD, Alan KALITSOV
  • Publication number: 20210327484
    Abstract: A magnetoresistive 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 may include a ferroelectric material layer and a metamagnetic tunnel junction containing a metamagnetic material layer, an insulating barrier layer, and a metallic material layer. Alternatively, the layer stack may include a multiferroic material layer, the metamagnetic material layer, the insulating barrier layer, and a reference magnetization layer.
    Type: Application
    Filed: April 20, 2020
    Publication date: October 21, 2021
    Inventors: Bhagwati PRASAD, Alan KALITSOV
  • Patent number: 11152048
    Abstract: A magnetoresistive 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 may include a ferroelectric material layer and a metamagnetic tunnel junction containing a metamagnetic material layer, an insulating barrier layer, and a metallic material layer. Alternatively, the layer stack may include a multiferroic material layer, the metamagnetic material layer, the insulating barrier layer, and a reference magnetization layer.
    Type: Grant
    Filed: April 20, 2020
    Date of Patent: October 19, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov
  • Publication number: 20210320245
    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: Application
    Filed: June 25, 2021
    Publication date: October 14, 2021
    Inventors: Alan KALITSOV, Derek STEWART, Bhagwati PRASAD
  • Patent number: 11087791
    Abstract: A data storage drive includes a magnetic recording media comprising a ferroelectric layer between a bottom electrode layer and a top electrode layer. An applied voltage to the ferroelectric layer generates a strain that is transferred to a ferromagnetic recording layer formed proximate to the ferroelectric layer. The change in strain transferred to the recording layer changes the magnetic properties of the recording layer. A voltage can be selectively applied to all or part of the ferroelectric layer to place the ferromagnetic recording layer in a low coercivity state to assist in writing data. Voltage-assisted magnetic recording (VAMR) is provided based upon control of a magnetic recording media comprising a ferroelectric layer between a bottom electrode layer and a top electrode layer.
    Type: Grant
    Filed: May 5, 2020
    Date of Patent: August 10, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Alan Kalitsov, Kumar Srinivasan, Bhagwati Prasad
  • Publication number: 20210242279
    Abstract: A magnetic device includes a first electrode, a second electrode, a plurality of magnetic junctions each containing a ferromagnetic reference layer and a ferromagnetic free layer located between the first electrode and the second electrode, and a plurality of magnetoelectric multiferroic portions having different structural defect densities located between the first electrode and the second electrode. Each of the plurality of magnetoelectric multiferroic portions is magnetically coupled to the ferromagnetic free layer of a respective one of the plurality of magnetic junctions.
    Type: Application
    Filed: February 4, 2020
    Publication date: August 5, 2021
    Inventors: Bhagwati PRASAD, Alan KALITSOV
  • Patent number: 11069741
    Abstract: A magnetoresistive memory device includes a first electrode, a second electrode, and a layer stack containing an electric field-modulated magnetic transition layer and a ferroelectric insulator layer located between the first electrode and the second electrode, The electric field-modulated magnetic transition layer includes a non-metallic magnetic material having a ferromagnetic state and a non-ferromagnetic state with a state transition therebetween that depends on an external electric field.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: July 20, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov
  • Patent number: 11056640
    Abstract: Magnetoelectric or magnetoresistive memory cells include at least one of a high dielectric constant dielectric capping layer and/or a nonmagnetic metal dust layer located between the free layer and the dielectric capping layer.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: July 6, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Matthew Carey, Alan Kalitsov, Bruce Terris
  • Patent number: 11049538
    Abstract: A magnetoresistive memory device includes a magnetic tunnel junction comprising a free layer, a reference layer, and an insulating tunnel barrier layer located between the free layer and the reference layer, a perpendicular magnetic anisotropy (PMA) ferromagnetic layer that is vertically spaced from the free layer, an electrically conductive, non-magnetic interlayer exchange coupling layer located between the free layer and the PMA ferromagnetic layer. The magnetoresistive memory device is a hybrid magnetoresistive memory device which is programmed by a combination of a spin-torque transfer effect and a voltage-controlled exchange coupling effect.
    Type: Grant
    Filed: March 20, 2020
    Date of Patent: June 29, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Alan Kalitsov, Bhagwati Prasad
  • Publication number: 20210159392
    Abstract: Magnetoelectric or magnetoresistive memory cells include at least one of a high dielectric constant dielectric capping layer and/or a nonmagnetic metal dust layer located between the free layer and the dielectric capping layer.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 27, 2021
    Inventors: Bhagwati PRASAD, Matthew CAREY, Alan KALITSOV, Bruce TERRIS
  • Publication number: 20210159391
    Abstract: Magnetoelectric or magnetoresistive memory cells include at least one of a high dielectric constant dielectric capping layer and/or a nonmagnetic metal dust layer located between the free layer and the dielectric capping layer.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 27, 2021
    Inventors: Bhagwati PRASAD, Matthew Carey, Alan Kalitsov, Bruce Terris
  • Publication number: 20210151501
    Abstract: A magnetoresistive memory device includes a first electrode, a second electrode, and a layer stack containing an electric field-modulated magnetic transition layer and a ferroelectric insulator layer located between the first electrode and the second electrode, The electric field-modulated magnetic transition layer includes a non-metallic magnetic material having a ferromagnetic state and a non-ferromagnetic state with a state transition therebetween that depends on an external electric field.
    Type: Application
    Filed: November 18, 2019
    Publication date: May 20, 2021
    Inventors: Bhagwati PRASAD, Alan KALITSOV
  • Patent number: 11005034
    Abstract: Magnetoelectric or magnetoresistive memory cells include at least one of a high dielectric constant dielectric capping layer and/or a nonmagnetic metal dust layer located between the free layer and the dielectric capping layer.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: May 11, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Matthew Carey, Alan Kalitsov, Bruce Terris
  • Patent number: 10991407
    Abstract: Magnetoelectric or magnetoresistive memory cells include at least one of a high dielectric constant dielectric capping layer and/or a nonmagnetic metal dust layer located between the free layer and the dielectric capping layer.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: April 27, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Matthew Carey, Alan Kalitsov, Bruce Terris
  • Patent number: 10964748
    Abstract: A magnetoresistive memory device includes a first electrode, a second electrode, and a layer stack containing an electric field-modulated magnetic transition layer and a ferroelectric insulator layer located between the first electrode and the second electrode, The electric field-modulated magnetic transition layer includes a non-metallic magnetic material having a ferromagnetic state and a non-ferromagnetic state with a state transition therebetween that depends on an external electric field.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: March 30, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Bhagwati Prasad, Alan Kalitsov