Patents by Inventor Sarbanoo Das

Sarbanoo Das 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: 20150138937
    Abstract: A method of storing data includes providing a write signal for a write head of a hard disk drive, generating a transition pulse signal derived from the write signal using a transition pulse generator, and generating a logic signal to drive a thermal source associated with the write head of the hard disk drive. The logic signal includes the logical summation of a cyclical base pulse signal and the transition pulse signal.
    Type: Application
    Filed: November 15, 2013
    Publication date: May 21, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Naoto Ito, Michiya Kazusawa, Hiroyasu Tanabe, Sarbanoo Das, Hideki Zaitsu
  • Patent number: 9025420
    Abstract: A method of storing data includes providing a write signal for a write head of a hard disk drive, generating a transition pulse signal derived from the write signal using a transition pulse generator, and generating a logic signal to drive a thermal source associated with the write head of the hard disk drive. The logic signal includes the logical summation of a cyclical base pulse signal and the transition pulse signal.
    Type: Grant
    Filed: November 15, 2013
    Date of Patent: May 5, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Naoto Ito, Michiya Kazusawa, Hiroyasu Tanabe, Sarbanoo Das, Hideki Zaitsu
  • Patent number: 8817406
    Abstract: A magnetic-recording head with touch-down detector incorporating a carbon nano-tube (CNT). The magnetic-recording head includes a write element, a read element and a touch-down detector. The write element is configured to write data to a magnetic-recording disk. The read element is configured to read data from the magnetic-recording disk. The touch-down detector includes a thermal sensor, and a CNT portion. The thermal sensor is configured to convert heat to a voltage signal. The CNT portion is configured to touch down on the magnetic-recording disk. The CNT portion is also coupled to the thermal sensor, and is configured to transfer heat generated by contact between the CNT portion and the magnetic-recording disk to the thermal sensor. A hard-disk drive (HDD) including the magnetic-recording head with touch-down detector incorporating a CNT, and a method for detecting contact between the magnetic-recording head and a recording surface of a magnetic-recording disk are also provided.
    Type: Grant
    Filed: December 30, 2011
    Date of Patent: August 26, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Patent number: 8786984
    Abstract: In one embodiment, a magnetic head includes a main pole configured to produce a magnetic writing field applied to a magnetic medium at an overall angle with respect to a magnetic anisotropy axis which is oriented in a direction perpendicular to a plane of a surface of the magnetic medium, and at least one current carrying element positioned near a media facing surface of the main pole configured to produce an assisting magnetic field applied in a cross-track direction parallel to the plane of the surface of the magnetic medium. In another embodiment, a method includes applying a writing magnetic field to write data to a magnetic medium and applying an assisting magnetic field to the magnetic medium for assisting the writing magnetic field, the assisting magnetic field being applied in a cross-track direction of the magnetic medium and parallel to a plane of a surface of the magnetic medium.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: July 22, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Patent number: 8760801
    Abstract: In one embodiment a magnetic head includes a sensor thin film adapted for producing a planar Hall voltage, the sensor thin film having a thickness along a down-track direction that is greater than a thickness along a cross-track direction. The down-track direction is in a direction of travel of a magnetic medium relative to the sensor thin film, and the cross-track direction is perpendicular to the down-track direction. In another embodiment, at least one magnetic head as described above is included in a magnetic data storage system, which includes a magnetic medium, a drive mechanism for passing the magnetic medium over the at least one magnetic head, and a controller electrically coupled to the at least one magnetic head for controlling operation of the at least one magnetic head. Other heads and systems are described according to various other embodiments.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: June 24, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Publication number: 20130170070
    Abstract: A magnetic-recording head with touch-down detector incorporating a carbon nano-tube (CNT). The magnetic-recording head includes a write element, a read element and a touch-down detector. The write element is configured to write data to a magnetic-recording disk. The read element is configured to read data from the magnetic-recording disk. The touch-down detector includes a thermal sensor, and a CNT portion. The thermal sensor is configured to convert heat to a voltage signal. The CNT portion is configured to touch down on the magnetic-recording disk. The CNT portion is also coupled to the thermal sensor, and is configured to transfer heat generated by contact between the CNT portion and the magnetic-recording disk to the thermal sensor. A hard-disk drive (HDD) including the magnetic-recording head with touch-down detector incorporating a CNT, and a method for detecting contact between the magnetic-recording head and a recording surface of a magnetic-recording disk are also provided.
    Type: Application
    Filed: December 30, 2011
    Publication date: July 4, 2013
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Publication number: 20130120869
    Abstract: In one embodiment, a magnetic head includes a main pole configured to produce a magnetic writing field applied to a magnetic medium at an overall angle with respect to a magnetic anisotropy axis which is oriented in a direction perpendicular to a plane of a surface of the magnetic medium, and at least one current carrying element positioned near a media facing surface of the main pole configured to produce an assisting magnetic field applied in a cross-track direction parallel to the plane of the surface of the magnetic medium. In another embodiment, a method includes applying a writing magnetic field to write data to a magnetic medium and applying an assisting magnetic field to the magnetic medium for assisting the writing magnetic field, the assisting magnetic field being applied in a cross-track direction of the magnetic medium and parallel to a plane of a surface of the magnetic medium.
    Type: Application
    Filed: November 15, 2011
    Publication date: May 16, 2013
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Patent number: 8390954
    Abstract: According to one embodiment, magnetic reproducing element for detecting a magnetic field from a magnetic recording medium comprises a sensor film including a perpendicular magnetization film having a magnetization easy axis in a direction perpendicular to a film plane, wherein magnetization in the sensor film tilts upward or downward in an element height direction from the magnetization easy axis while no magnetic field is applied from the magnetic recording medium, and change in anomalous Hall voltage generated in the sensor film is detected, thereby allowing the magnetic field applied from the magnetic recording medium to be detected. Other magnetic reproducing elements and magnetic heads employing magnetic reproducing elements are described as well.
    Type: Grant
    Filed: September 9, 2009
    Date of Patent: March 5, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Sarbanoo Das, Masae Suzuki
  • Publication number: 20120162810
    Abstract: In one embodiment a magnetic head includes a sensor thin film adapted for producing a planar Hall voltage, the sensor thin film having a thickness along a down-track direction that is greater than a thickness along a cross-track direction. The down-track direction is in a direction of travel of a magnetic medium relative to the sensor thin film, and the cross-track direction is perpendicular to the down-track direction. In another embodiment, at least one magnetic head as described above is included in a magnetic data storage system, which includes a magnetic medium, a drive mechanism for passing the magnetic medium over the at least one magnetic head, and a controller electrically coupled to the at least one magnetic head for controlling operation of the at least one magnetic head. Other heads and systems are described according to various other embodiments.
    Type: Application
    Filed: December 22, 2010
    Publication date: June 28, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands B.V
    Inventors: Sarbanoo Das, Masafumi Mochizuki
  • Publication number: 20100061014
    Abstract: According to one embodiment, magnetic reproducing element for detecting a magnetic field from a magnetic recording medium comprises a sensor film including a perpendicular magnetization film having a magnetization easy axis in a direction perpendicular to a film plane, wherein magnetization in the sensor film tilts upward or downward in an element height direction from the magnetization easy axis while no magnetic field is applied from the magnetic recording medium, and change in anomalous Hall voltage generated in the sensor film is detected, thereby allowing the magnetic field applied from the magnetic recording medium to be detected. Other magnetic reproducing elements and magnetic heads employing magnetic reproducing elements are described as well.
    Type: Application
    Filed: September 9, 2009
    Publication date: March 11, 2010
    Inventors: Sarbanoo Das, Hiroyuki Suzuki, Masae Suzuki