Patents by Inventor Julius K. Hohlfeld

Julius K. Hohlfeld 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).

  • Measuring transition shifts due to laser power variation in a heat-assisted magnetic recording device
    Patent number: 9818447
    Abstract: A method comprises writing a waveform on a magnetic recording medium using a heat-assisted magnetic recording apparatus which includes a laser. The method also comprises reading back the waveform from the medium, and detecting one or more transition shifts in the readback waveform indicative of a mode hop of the laser. The method further comprises measuring a metric of the one or more transition shifts.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: November 14, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Xuan Zheng, Walter R. Eppler, Julius K. Hohlfeld, Heidi M. Olson
  • Measuring transition shifts due to laser power variation in a heat-assisted magnetic recording device
    Patent number: 9620163
    Abstract: A method comprises writing a waveform on a magnetic recording medium using a heat-assisted magnetic recording apparatus which includes a laser. The method also comprises reading back the waveform from the medium, and detecting one or more transition shifts in the readback waveform indicative of a mode hop of the laser. The method further comprises measuring a metric of the one or more transition shifts.
    Type: Grant
    Filed: May 16, 2016
    Date of Patent: April 11, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Xuan Zheng, Walter R. Eppler, Julius K. Hohlfeld, Heidi M. Olson
  • Patterned heat sink layer for eliminating lateral thermal bloom
    Patent number: 9207024
    Abstract: The embodiments disclose at least one predetermined patterned layer configured to eliminate a physical path of lateral thermal bloom in a recording device, at least one gradient layer coupled to the patterned layer and configured to use materials with predetermined thermal conductivity for controlling a rate of dissipation and a path coupled to the gradient layer and configured to create a path of least thermal conduction resistance for directing dissipation along the path, wherein the path substantially regulates and prevents lateral thermal bloom.
    Type: Grant
    Filed: October 16, 2013
    Date of Patent: December 8, 2015
    Assignee: Segate Technology LLC
    Inventors: Ganping Ju, Xiaobin Zhu, Chubing Peng, Yukiko A. Kubota, Yingguo Peng, Timothy J. Klemmer, Jan-Ulrich Thiele, David S. Kuo, Bin Lu, Julius K. Hohlfeld
  • METHOD FOR FABRICATING PATTERNED GRADIENT HEAT SINKS
    Publication number: 20150013946
    Abstract: The embodiments disclose at least one predetermined patterned layer configured to eliminate a physical path of lateral thermal bloom in a recording device, at least one gradient layer coupled to the patterned layer and configured to use materials with predetermined thermal conductivity for controlling a rate of dissipation and a path coupled to the gradient layer and configured to create a path of least thermal conduction resistance for directing dissipation along the path, wherein the path substantially regulates and prevents lateral thermal bloom.
    Type: Application
    Filed: October 16, 2013
    Publication date: January 15, 2015
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Ganping Ju, Xiaobin Zhu, Chubing Peng, Yukiko A. Kubota, Yingguo Peng, Timothy J. Klemmer, Jan-Ulrich Thiele, David S. Kuo, Bin Lu, Julius K. Hohlfeld
  • Thin film structure with controlled lateral thermal spreading in the thin film
    Patent number: 8576515
    Abstract: An apparatus includes a non-metallic interlayer between a magnetic data storage layer and a heat sink layer, wherein interface thermal resistance between the interlayer and the heat sink layer is capable of reducing heat flow between the heat sink layer and the magnetic data storage layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include thermal resistor layer positioned between the interlayer and the heat sink layer.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: November 5, 2013
    Assignee: Seagate Technology LLC
    Inventors: Julius K. Hohlfeld, Bin Lu, Ganping A. Ju, Amit V. Itagi, Timothy Klemmer, Yingguo Peng, Yukiko Kubota
  • THIN FILM STRUCTURE WITH CONTROLLED LATERAL THERMAL SPREADING IN THE THIN FILM
    Publication number: 20120194942
    Abstract: An apparatus includes a non-metallic interlayer between a magnetic data storage layer and a heat sink layer, wherein interface thermal resistance between the interlayer and the heat sink layer is capable of reducing heat flow between the heat sink layer and the magnetic data storage layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include thermal resistor layer positioned between the interlayer and the heat sink layer.
    Type: Application
    Filed: March 30, 2012
    Publication date: August 2, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Julius K. Hohlfeld, Bin Lu, Ganping Ju, Amit V. Itagi, Timothy Klemmer, Yingguo Peng, Yukiko Kubota
  • Thin film structure with controlled lateral thermal spreading in the thin film
    Patent number: 8149539
    Abstract: An apparatus includes a magnetic layer, a heat sink layer, and a thermal resistor layer between the magnetic layer and the heat sink layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include an interlayer positioned between the magnetic layer and the thermal resistor layer.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: April 3, 2012
    Assignee: Seagate Technology LLC
    Inventors: Bin Lu, Ganping A. Ju, Julius K. Hohlfeld, Duane C. Karns, Amit V. Itagi, William A. Challener, Hua Zhou
  • Thin Film Structure With Controlled Lateral Thermal Spreading In The Thin Film
    Publication number: 20110096432
    Abstract: An apparatus includes a magnetic layer, a heat sink layer, and a thermal resistor layer between the magnetic layer and the heat sink layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include an interlayer positioned between the magnetic layer and the thermal resistor layer.
    Type: Application
    Filed: December 8, 2010
    Publication date: April 28, 2011
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Bin Lu, Ganping Ju, Julius K. Hohlfeld, Duane C. Karns, Amit V. Itagi, William A. Challener, Hua Zhou
  • Thin film structure with controlled lateral thermal spreading in the thin film
    Patent number: 7869162
    Abstract: An apparatus includes a magnetic layer, a heat sink layer, and a thermal resistor layer between the magnetic layer and the heat sink layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include an interlayer positioned between the magnetic layer and the thermal resistor layer.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: January 11, 2011
    Assignee: Seagate Technology LLC
    Inventors: Bin Lu, Ganping Ju, Julius K. Hohlfeld, Duane C. Karns, Amit V. Itagi, William A. Challener, Hua Zhou
  • Thin film structure with controlled lateral thermal spreading in the thin film
    Publication number: 20080198738
    Abstract: An apparatus includes a magnetic layer, a heat sink layer, and a thermal resistor layer between the magnetic layer and the heat sink layer. The apparatus may be configured as a thin film structure arranged for data storage. The apparatus may also include an interlayer positioned between the magnetic layer and the thermal resistor layer.
    Type: Application
    Filed: February 16, 2007
    Publication date: August 21, 2008
    Applicant: Seagate Technology LLC
    Inventors: Bin Lu, Ganping Ju, Julius K. Hohlfeld, Duane C. Karns, Amit V. Itagi, William A. Challener, Hua Zhou