Thermomagnetic Recording Or Transducers Patents (Class 360/59)
  • Patent number: 9070397
    Abstract: A data storage device and method for improved flying height control (TFC) in a HAMR or MAMR system employing three heat sources to control the head protrusion: write coil current, TFC heater current, and media exciter power. The TFC heater is used to pre-heat the write head. The media exciter may be operated at a either a zero level or a low level below that required for the HAMR or MAMR process, optionally serving as an additional source of heat to the write head. The HAMR or MAMR data writing process commences only after the head protrusion has been increased and stabilized. During data writing, the media exciter power is increased to the higher level required to heat the disk medium in an HAMR or MAMR process and the TFC heater power is slightly reduced to maintain the total heat into the head approximately constant.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: June 30, 2015
    Assignee: HGST NETHERLANDS B.V.
    Inventors: Naoto Ito, Jun Hashimoto, Erhard Schreck, Michiya Kazusawa
  • Patent number: 9070398
    Abstract: Provided is a magnetic recording medium including a structure in which at least a soft magnetic underlayer, a non-magnetic intermediate layer, and a magnetic recording layer are sequentially laminated on a non-magnetic substrate, wherein the magnetic recording layer includes a first magnetic layer, a non-magnetic layer, and a second magnetic layer in order from the non-magnetic substrate side, has a structure in which the first magnetic layer and the second magnetic layer are magnetically separated from each other with the non-magnetic layer interposed therebetween, and consists of a plurality of patterns which are magnetically separated from each other, and the coercive force Hc of the second magnetic layer is larger than that of the first magnetic layer, and the coercive force Hc of the second magnetic layer is smaller than that of the first magnetic layer temporarily when the second magnetic layer is heated.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: June 30, 2015
    Assignee: SHOWA DENKO K.K.
    Inventors: Akira Sakawaki, Akira Yamane
  • Patent number: 9047912
    Abstract: A write head includes a three-dimensional waveguide extending along a light-propagation direction. The three-dimensional waveguide is configured to receive light from a light source at a fundamental transverse electric (TE) mode. The three-dimensional waveguide includes an input coupler, a curved middle section, and a terminating end. The input coupler is tapered between the light source and the curved middle section. The write head includes a dual-mode waveguide extending along the light propagation direction and has an edge proximate to and separated from the curved section by a gap at a coupling region. The three-dimensional waveguide excites a higher-order TE mode in the dual-mode waveguide via the coupling region.
    Type: Grant
    Filed: September 22, 2014
    Date of Patent: June 2, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Chubing Peng, Yi-Kuei Ryan Wu
  • Patent number: 9047894
    Abstract: A magnetic write head having a write pole with a tapered trailing edge portion and having a spin torque oscillator that is formed entirely on the tapered trailing edge portion and that is self aligned with first and second sides of the write pole. The write pole and spin torque oscillator are formed by a method wherein the sides of the spin torque oscillator and write pole are defined in the same photolithographic and ion milling process, thereby allowing for the self alignment of the spin torque oscillator with the sides of the write pole.
    Type: Grant
    Filed: October 3, 2013
    Date of Patent: June 2, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Andrew Chiu, Edward H. P. Lee
  • Patent number: 9042207
    Abstract: Controlling a laser diode involves activating a first current source in preparation for writing to a magnetic recording medium. The first current source applies a threshold current to a laser diode that brings the laser diode close to an operating point. Responsive to a write signal, a second current source is activated that applies a write current to the laser diode. A combination of the write current and the threshold current fully energizes the laser diode and is less than a target recording current. Coincident with the activation of the second current source, a photodiode is activated that is optically coupled to the laser diode. The activated photodiode causes a feedback current to be applied to the laser diode.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: May 26, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventor: Housan Dakroub
  • Patent number: 9042048
    Abstract: The present disclosure generally relates to a HAMR head and a method for fabrication thereof. The HAMR head has a write head with a waveguide extending therethrough. A laser diode is coupled to a submount that is bonded to the write head using an adhesion layer, a solder structure, and a self-propagating multilayer alloying stack.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: May 26, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventor: Alan H. Brothers
  • Patent number: 9036307
    Abstract: A heat-assisted magnetic recording (HAMR) air-bearing slider has an optically-transparent protective film over the near-field transducer (NFT) to protect the NFT from excessive heat caused by the accumulation of carbonaceous material on the slider's overcoat. The NFT is thus separated from the overcoat by the protective film. The protective film does not cover the write pole end, which is covered only by the overcoat, so there is no spacing loss between the write pole end and the recording layer on the disk. In one embodiment the protective film is coplanar with the recording-layer-facing surface of the slider and the overcoat covers both the protective film and the write pole end. In another embodiment the overcoat has a window that surrounds the protective film, with the protective film being substantially coplanar with the air-bearing surface (ABS) of the slider. In both embodiments the smooth topography of the slider's ABS is maintained.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: May 19, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Hiroyuki Hoshiya, Tomomitsu Inoue, Tetsuya Matsusaki, Harukazu Miyamoto, Kazuhito Miyata, Kentaro Namikawa, Atsuko Okawa
  • Patent number: 9030773
    Abstract: An apparatus includes a near-field transducer at or near an air bearing surface of the apparatus. A write pole is disposed at or near the air bearing surface and proximate the near-field transducer, respectively. A thermal sensor is disposed at the air bearing surface and within a protrusion region of the air bearing surface defined relative to at least one of the near-field transducer and the write pole. The thermal sensor is configured to produce a signal indicative of a temperature at the protrusion region.
    Type: Grant
    Filed: September 15, 2014
    Date of Patent: May 12, 2015
    Assignee: Seagate Technology LLC
    Inventors: Declan Macken, James Dillon Kiely, Manuel Charles Anaya-Dufresne
  • 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: 9019646
    Abstract: An apparatus includes a write element configured to apply a magnetic field to write data on a portion of a heat-assisted magnetic recording media in response to an energizing current. An energy source is configured to heat the portion of the media being magnetized by the write element. A preheat energizing current is applied to the write element during an interval before writing the data to the portion of the media. The preheat energizing current does not cause data to be written to the media and brings at least one of the write element and driver circuitry into thermal equilibrium prior to writing the data on the portion.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 28, 2015
    Assignee: Seagate Technology LLC
    Inventors: Tim Rausch, Jon D. Trantham, John West Dykes, Housan Dakroub, Charles Paul Henry, Edward Charles Gage, Raul Horacio Andruet, James Gary Wessel, James Dillon Kiely, Bruce Douglas Buch, Barmeshwar Vikramaditya
  • Patent number: 9013820
    Abstract: Devices and methods for reducing thermal stress within a head of a storage device are disclosed. In one or more embodiments, a method includes writing a selected pattern to a storage medium of a storage device using a head of the storage device; reading the selected pattern from the storage medium using the head to provide a data signal; and calculating an instability value of the head based on the data signal. The method can further include reconfiguring the storage device if the instability value is greater than an instability threshold by performing at least one of: deactivating a heater if the head includes two or more heaters; and increasing a fly height between the head and the storage medium.
    Type: Grant
    Filed: April 23, 2014
    Date of Patent: April 21, 2015
    Assignee: Seagate Technology LLC
    Inventors: Clifford Jayson Bringas Camalig, Gan Swee Chuan, Kai K. Yang, Mui Chong Chai
  • Patent number: 9013967
    Abstract: In a heat-assisted magnetic recording (HAMR) hard disk drive, a heat-dissipating head slider assembly is described in which the slider is stepped on the disk-opposing side and a HAMR laser module is mounted on the lower surface to assist with dissipation of heat from the laser. The lower surface is a surface of the main body of the slider and is composed primarily of a first material, and the slider may include a heat-dissipating plate that forms the higher stepped surface, where the plate is composed of a second material that has a higher thermal conductivity than the first material, such as silicon.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: April 21, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Shigeo Nakamura, Irizo Naniwa, Harukazu Miyamoto, Tomoaki Uno
  • Publication number: 20150103430
    Abstract: A bond pad set includes at least one ground pad and at least one electrical bond pad configured to bias and send/receive signals. The bond pad set is electrically connected to a multiplicity of electrical components. At least one electrical bond pad of the bond pad set is shared between two or more of the electrical components.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 16, 2015
    Applicant: Seagate Technology LLC
    Inventors: Jason Bryce Gadbois, Declan Macken, Karsten Klarqvist
  • Publication number: 20150103431
    Abstract: Embodiments described herein generally relate to a magnetic recording device for recording/reproducing data using the magnetization state of a recording medium. More specifically, embodiments described herein provide an STO structure having an SPL and an FGL with an anti-ferromagnetic coupling interlayer disposed between the SPL and FGL. The anti-ferromagnetic coupling interlayer may enable the STO structure to obtain a high assist effect even when operated with a low conducting current.
    Type: Application
    Filed: October 11, 2013
    Publication date: April 16, 2015
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Masukaza IGARASHI, Keiichi NAGASAKA, Masato SHIIMOTO
  • Patent number: 9007713
    Abstract: A medium may be provided. The medium includes a servo layer, a data recording layer, and a heat sink layer disposed between the servo layer and the recording layer.
    Type: Grant
    Filed: September 23, 2014
    Date of Patent: April 14, 2015
    Assignee: Marvell International Ltd.
    Inventors: Zhimin Yuan, Bo Liu, Jianzhong Shi, Weidong Zhou
  • Patent number: 9001629
    Abstract: Systems and methods for suppressing the background energy of a waveguide in an EAMR system are provided. One such system includes a near field transducer having a disk section and a pin section extending from the disk section to an air bearing surface of a slider, a waveguide having a core and a cladding, where the waveguide is configured to couple light energy to the near field transducer, where the cladding is configured to substantially surround the core, and a recess portion positioned between the core and the air bearing surface.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: April 7, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Hongxing Yuan, Ronald L. Allen, Michael V. Morelli, Matthew R. Gibbons, Zhong Shi
  • Patent number: 9001628
    Abstract: A heat assisted magnetic recording (HAMR) transducer on a slider and including first and second opposing surfaces, wherein the first surface is aligned to an air bearing surface (ABS) of the slider and the second surface is aligned to a surface of the slider opposite the ABS, a target waveguide having an entrance at the second surface, the target waveguide being configured to direct energy provided by a light source from the entrance toward the first surface, wherein the target waveguide expands in cross-section area with distance from the entrance to form an inverse taper waveguide, a plurality of assistant waveguides each having an entrance at the second surface, wherein the plurality of assistant waveguides are configured to direct energy to the plurality of output devices.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: April 7, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Zhong Shi, Paul Lin, Michael V. Morelli, Weigang Wang
  • Publication number: 20150092292
    Abstract: Embodiments of the present invention generally relate to a microwave assisted magnetic recording (MAMR) head. The MAMR head includes a main pole, a trailing shield, and a spin torque oscillator (STO) disposed between the main pole and the trailing shield. The STO is recessed from an air bearing surface.
    Type: Application
    Filed: September 27, 2013
    Publication date: April 2, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Masaru FURUKAWA, Jianhua LI, Masato MATSUBARA, Masato SHIIMOTO
  • Patent number: 8995079
    Abstract: According to one embodiment, there is provided a magnetic head including a wave guide, a near field transducer, a writing magnetic pole, a magnetic core, a writing coil, and a first temperature control element. The near field transducer is disposed on an ABS surface and to which light is guided from the wave guide. The writing magnetic pole is disposed on the ABS surface. The magnetic core is connected to the writing magnetic pole so as to generate a magnetic field from a portion of the writing magnetic pole close to the ABS surface. The writing coil is disposed so as to go around the magnetic core. The first temperature control element is disposed in contact with a region of a first side surface of the wave guide near the near field transducer.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: March 31, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Isokawa, Tomoko Taguchi
  • Patent number: 8995076
    Abstract: An apparatus of the present disclosure generally includes a recording head, circuitry, a thermal sensor, and a detector. The recording head has an electromagnetic attraction to a recording medium. The circuitry is configured to oscillate the electromagnetic attraction between the recording head and the recording medium. The oscillating electromagnetic attraction produces a corresponding oscillating clearance between the recording head and the recording medium. The thermal sensor, located in or near the recording head, senses an oscillating temperature that is induced by the oscillating clearance and produces a sensor signal that is representative of the sensed temperature. The detector is coupled to the thermal sensor and is configured to detect at least one of head-medium contact and clearance using the sensor signal and the electromagnetic attraction.
    Type: Grant
    Filed: April 21, 2014
    Date of Patent: March 31, 2015
    Assignee: Seagate Technology LLC
    Inventors: Daniel W. Olson, David J. Ellison, Michael Thomas Johnson
  • Patent number: 8988813
    Abstract: A microwave-assisted magnetic recording and reproducing apparatus includes a microwave power generator, a microwave magnetic field generating element, and a thin film magnetic head that may record a data signal in high density in a magnetic recording medium that has a high coercivity. A magnetic recording medium, a magnetic head that records information in the magnetic recording medium, a microwave power generator provided independently of the magnetic head, and a differential signal supply unit used to supply microwave power generated by the microwave power generator as differential signals to a microwave magnetic field generating element provided at the magnetic head are included.
    Type: Grant
    Filed: May 19, 2014
    Date of Patent: March 24, 2015
    Assignee: TDK Corporation
    Inventor: Eriko Ajioka
  • Patent number: 8988975
    Abstract: A thermally assisted magnetic head includes a main magnetic pole layer, a near-field light generating layer having a generating end part generating near-field light arranged within a medium-opposing surface, and an optical waveguide guiding light to the near-field light generating layer. The near-field light generating layer has a laminated structure in which a first thin-film metal layer formed in a thin film form along a direction intersecting the medium-opposing surface and a second thin-film metal layer formed in a thin film form and formed using a second metal larger in hardness than a first metal forming the first thin-film metal layer are alternately laminated. Further, in the second thin-film metal layer, a defect part is formed, the defect part is a part smaller in thickness than another part or is a hole part, and a flat layer part other than the defect part surrounds the defect part.
    Type: Grant
    Filed: September 24, 2013
    Date of Patent: March 24, 2015
    Assignees: Headyway Technologies, Inc., SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshitaka Sasaki, Hiroyuki Ito, Hironori Araki, Shigeki Tanemura, Kazuki Sato, Ryuji Fujii
  • Patent number: 8984739
    Abstract: A method of manufacturing a thermally-assisted magnetic recording head includes the steps of: forming a preliminary head section that has a surface to be polished and includes a magnetic pole, a waveguide, and a preliminary plasmon generator; causing a volumetric expansion of the preliminary plasmon generator with heat by introducing light into the core of the waveguide of the preliminary head section; and polishing the surface to be polished of the preliminary head section into a medium facing surface. The preliminary plasmon generator has an end face located in the surface to be polished. In the step of polishing the surface to be polished, the surface to be polished is subjected to polishing with the preliminary plasmon generator expanded in volume, whereby the end face of the preliminary plasmon generator is polished into the front end face, and the preliminary plasmon generator thereby becomes the plasmon generator.
    Type: Grant
    Filed: October 14, 2011
    Date of Patent: March 24, 2015
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Koji Shimazawa, Yasutoshi Fujita, Tatsuya Shimizu
  • Patent number: 8982494
    Abstract: A head gimbal assembly has a suspension configured to extend along a surface of a recording medium and to bend and deform in a thickness direction of the recording medium. A slider is provided on a front end side of the suspension so as to confront the surface of the recording medium. A support section supports the slider such that the slider can pivot about two axes parallel to the surface of the recording medium and perpendicular to each other. An optical waveguide is connected to the slider and is configured to introduce a light flux into the slider. A near-field light generating element generates near-field light from the optical flux and causes the near-field light to record information on the recording medium. A positioning section is mounted between the support section and the slider for positioning the optical waveguide relative to the slider.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: March 17, 2015
    Assignee: Seiko Instruments Inc.
    Inventors: Masakazu Hirata, Manabu Oumi, Majung Park, Sachiko Tanabe
  • Patent number: 8982678
    Abstract: A data storage media may have at least a multi-layer recording lamination with a predetermined coercivity. The multi-layer recording lamination can be configured to record at least one servo format mark for a plurality of data tracks with a solid immersion mirror and program a data bit on the multi-layer recording lamination with a near field transducer.
    Type: Grant
    Filed: April 9, 2012
    Date of Patent: March 17, 2015
    Assignee: Seagate Technology LLC
    Inventors: Edward Charles Gage, Jan-Ulrich Thiele
  • Patent number: 8971159
    Abstract: A light delivery system in a slider includes a channel waveguide, a mode-index refractive surface, a solid immersion mirror, and a near field transducer. The mode-index refractive surface shapes the angular spectrum of the light on its path to the solid immersion mirror in a manner so as to change the distribution of light energy focused on to the near field transducer.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: March 3, 2015
    Assignee: Seagate Technology LLC
    Inventors: Bernard W. Bell, Chubing Peng
  • Patent number: 8958168
    Abstract: A method and system provides an EAMR transducer. The transducer is coupled with a laser for providing energy and has an air-bearing surface (ABS) configured to reside in proximity to a media during use. The EAMR transducer includes a composite near field transducer (NFT), a write pole and at least one coil for energizing the write pole. The write pole is configured to write to a region of the media. The composite NFT is for focusing the energy onto the region of the media. The composite NFT includes at least one metal and at least one insulator therein.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: February 17, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Hongxing Yuan, Zhongyan Wang, Michael V. Morelli, Ronald L. Allen
  • Patent number: 8953420
    Abstract: Light is guided from a light source into a waveguide coupler embedded in a slider. The light source is capable of being positioned in a cross-track, a down-track, and a vertical direction with regards to the waveguide coupler. The light emanating from an air-bearing surface of the slider is imaged using a device that generates an optical image of the air-bearing surface. A cross-track alignment position is identified as a location at which the image shows substantially the same number of photons on each side of the cross-track alignment position and has a minimum spread. A down-track alignment position is identified at which the light emanating from the air-bearing surface has maximal intensity in a down-track direction.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: February 10, 2015
    Assignee: Seagate Technology LLC
    Inventor: Chubing Peng
  • Patent number: 8953272
    Abstract: An apparatus includes a waveguide configured to deliver light to a transducer region. The apparatus also includes a plasmonic transducer that has two metal elements configured as side-by-side plates on a substrate-parallel plane with a gap therebetween. The gap is disposed along the substrate-parallel plane and has an input end disposed proximate the transducer region and an output end. The transducer is configured to provide a surface plasmon-enhanced near-field radiation pattern proximate the output end in response to the light received by the waveguide.
    Type: Grant
    Filed: September 2, 2014
    Date of Patent: February 10, 2015
    Assignee: Seagate Technology LLC
    Inventors: Chubing Peng, Kaizhong Gao, Lien Lee, Amit Itagi, Michael Allen Seigler, Yimin Niu, Sethuraman Jayashankar
  • Patent number: 8947985
    Abstract: A heat assisted magnetic recording (HAMR) write transducer has an air-bearing surface (ABS) configured to reside in proximity to a media during use and is coupled with a laser that provides energy. The HAMR transducer includes a main pole, at least one additional pole adjacent to the main pole in a down track direction, a waveguide and at least one coil for energizing the main pole. The main pole is configured to write to a region of the media and is recessed from the ABS by a first distance. The additional pole(s) are recessed from the ABS by a second distance greater than the first distance. The waveguide is optically coupled with the laser and directs a portion of the energy toward the ABS at an acute angle from the ABS. A portion of the waveguide resides between the additional pole(s) and the ABS.
    Type: Grant
    Filed: September 23, 2013
    Date of Patent: February 3, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Michael V. Morelli, Lisha Wang, Zhigang Bai, Hongxing Yuan, Yunfei Li, Zhanjie Li, Matthew R. Gibbons, Samuel W. Yuan
  • Patent number: 8945733
    Abstract: A magnetic recording medium in which information can be recorded using a heat-assisted magnetic recording method comprises a recording layer formed on a substrate. The recording layer has a plurality of magnetic recording bit regions and a plurality of high thermal conductors each extending inside a corresponding one of the bit regions. The high thermal conductors have a thermal conductivity higher than that of the recording layer and assist in dissipating heat energy imparted to the bit regions during the recording of information.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: February 3, 2015
    Assignee: Seiko Instruments Inc.
    Inventors: Yoshikazu Tanaka, Norio Chiba, Manabu Oumi, Masakazu Hirata, Yoko Shinohara, Sachiko Tanabe
  • Patent number: 8937783
    Abstract: A magnetic data recording system wherein the wherein adjacent track interference during writing is avoided by modulating the size of a write bubble on the magnetic media in response to a position error signal. If the position error signal indicates that the magnetic head is off-track, circuitry within the magnetic data recording system adjusts the size of the write bubble temporarily to prevent the write bubble from encroaching on a neighboring data track. This adjustment of the write bubble can be accomplished by adjusting power to the write head. Adjustment of the write bubble can also be achieved by adjusting power to a magnetic oscillator in a microwave assisted magnetic recording system (MAMR) or adjusting power to a heating element in a thermally assisted magnetic recording system.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: January 20, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Thomas R. Albrecht, Manfred E. Schabes
  • Patent number: 8929016
    Abstract: A magnetic recording head includes a magnetic writer comprising a main write pole and a return write pole. The magnetic recording head includes a write heater assembly comprising at least one first heater subassembly and at least one second heater subassembly. At least part of the magnetic write head is disposed between the first heater subassembly and the second heater subassembly. When the first heater subassembly, the second heater subassembly, and the magnetic writer are energized, a variation in the thermal protrusion of the head media interface of the magnetic recording head may be less than about 20 nm along the down track and/or cross track directions.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: January 6, 2015
    Assignee: Seagate Technology LLC
    Inventors: Kaizhong Gao, Raul Horacio Andruet, Xiaobin Wang
  • Patent number: 8929013
    Abstract: A storage system with pattern dependent write includes a magnetic write head, a magnetic storage medium, a read channel operable to process write data to be recorded on the magnetic storage medium by the magnetic write head, and a preamplifier operable to receive the write data and an associated clock from the read channel, to generate a pattern dependent write control signal based on a pattern in the write data and on the clock, and to set a write current level through the magnetic write head to a number of different current levels based on the pattern dependent write control signal.
    Type: Grant
    Filed: November 21, 2013
    Date of Patent: January 6, 2015
    Assignee: LSI Corporation
    Inventors: Angelo R. Mastrocola, David W. Kelly, Ross S. Wilson, Jason P. Brenden
  • Publication number: 20140362674
    Abstract: A system includes a magnetic head, a magnetic medium, a drive mechanism for passing the magnetic medium over the magnetic head, and a controller electrically coupled to the magnetic head for controlling operation of the magnetic head, wherein the magnetic head has a write element, a read element, a substrate that is an alloy material having greater than about 50 at. % TiC, and a heater element positioned between the read element and the write element, the write element being positioned nearer to the substrate than the read element such that heat generated by the write element during write operations is dissipated by the substrate, and the heater element being adapted for inducing protrusion of portions of an air bearing surface (ABS) of the magnetic head to adjust a clearance between the portions of the ABS and the magnetic medium.
    Type: Application
    Filed: June 11, 2013
    Publication date: December 11, 2014
    Inventors: Koji Tanaka, Yoshinori Takeuchi
  • Patent number: 8896947
    Abstract: According to one embodiment, a disk storage apparatus includes a magnetic head, a detector, a calculator, and a decision module. The magnetic head has a high-frequency assisted element disposed close to a main magnetic pole that generates a recording magnetic field for perpendicular magnetic recording, the high-frequency assisted element applying a high-frequency magnetic field onto a magnetic disk during data recording. The detector detects an electrical resistance of the high-frequency assisted element. The calculator calculates time axis data indicative of a variation, on a time axis, in the electrical resistance value detected by the detector. The decision module determines whether the high-frequency assisted elements is malfunctioning based on the time axis data.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: November 25, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Gaku Koizumi, Masahiro Takashita, Tomoko Taguchi
  • Publication number: 20140340781
    Abstract: A microwave-assisted magnetic recording and reproducing apparatus includes a microwave power generator, a microwave magnetic field generating element, and a thin film magnetic head that may record a data signal in high density in a magnetic recording medium that has a high coercivity. A magnetic recording medium, a magnetic head that records information in the magnetic recording medium, a microwave power generator provided independently of the magnetic head, and a differential signal supply unit used to supply microwave power generated by the microwave power generator as differential signals to a microwave magnetic field generating element provided at the magnetic head are included.
    Type: Application
    Filed: May 19, 2014
    Publication date: November 20, 2014
    Applicant: TDK CORPORATION
    Inventor: Eriko AJIOKA
  • Publication number: 20140340782
    Abstract: A microwave-assisted magnetic head provides a high-reliability microwave-assisted magnetic head that reduces effective coercivity by giving microwave energy to a magnetic recording medium in an auxiliary manner and writes a data signal, a head gimbal assembly, and a magnetic recording and reproducing apparatus. A microwave magnetic field generating element is arranged on a trailing shield side or a reproducing head element side with respect to a main magnetic pole that generates a recording magnetic field for writing a data signal into a magnetic recording medium, the microwave magnetic field generating element having a coil configuration in which a plurality of microwave magnetic field generating lines and a return line are formed by a continuous single line.
    Type: Application
    Filed: May 19, 2014
    Publication date: November 20, 2014
    Applicant: TDK CORPORATION
    Inventor: Eriko AJIOKA
  • Patent number: 8891340
    Abstract: An apparatus and associated method is presently disclosed for a control circuitry capable of managing a heat source used in data storage applications. Various embodiments of the present invention are generally directed to a heat source directed at a data storage medium with a synchronization signal and a serial interface that are each selectively activated via a demultiplexed write gate signal. The selective activation allows for pulsed operation of the heat source resulting in reduced duty cycle and temperature during a write operation.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: November 18, 2014
    Assignee: Seagate Technology LLC
    Inventors: Michael H. Lennard, Robert Matousek
  • Patent number: 8885301
    Abstract: A crystal film with one or more nitrogen vacancy centers is placed in a magnetic field produced by a recording head and excitation illumination and a varying excitation field is applied. A confocal microscope or wide-field microscope optically detects a decrease in a spin dependent photoluminescence in response to the excitation illumination caused by electron spin resonance (ESR) of the at least one nitrogen vacancy center at varying excitation frequencies of the excitation field to measure Optically Detected Spin Resonance (ODMR). A characteristic of the recording head is determined using the ODMR.
    Type: Grant
    Filed: February 19, 2014
    Date of Patent: November 11, 2014
    Assignee: Infinitum Solutions, Inc.
    Inventor: Juergen Heidmann
  • Patent number: 8885280
    Abstract: Implementations disclosed herein allow a magneto-optical polarization rotator to couple light from a light source of a HAMR recording device to waveguide attached to a slider. According to one implementation, the magneto-optical polarization rotator has a magnetophotonic crystal structure with a number of thin film layers configured to rotate the light by 90 degrees.
    Type: Grant
    Filed: June 3, 2013
    Date of Patent: November 11, 2014
    Assignee: Seagate Technology LLC
    Inventors: Xiaoyue Huang, Karim Tatah, Ziyou Zhou
  • Publication number: 20140320993
    Abstract: Tape head with thermal tape-head distance sensor to reduce the distance between the tape and the head to allow an increase in areal density. A tape head designed for reading and/or writing to a tape, including: a tape bearing surface shaped to form an air bearing when moving the tape with respect to the tape bearing surface; a thermal tape-head distance sensor circuit adapted to sense heat dissipated at the level of the tape bearing surface by the tape and thereby sense a distance between the tape bearing surface and the tape; and tape-head distance control means connected to the thermal tape-head distance sensor circuit to receive a signal provided by the tape-head distance sensor circuit and configured to alter the distance according to a signal received from the tape-head distance sensor circuit. This invention is further directed to a method of tape-head distance control for the above tape head.
    Type: Application
    Filed: April 11, 2014
    Publication date: October 30, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Laurent A. Dellmann, Johan B. C. Engelen, Simeon Furrer, Mark Alfred Lantz, Hugo E. Rothuizen
  • Patent number: 8873185
    Abstract: The thermally-assisted magnetic recording head includes: a magnetic pole having an end exposed on an air-bearing surface; a waveguide; a plasmon generator formed essentially of a first metallic material, and having a first region and a second region, the first region extending backward from the air-bearing surface to a first position, and the second region being coupled with the first region at the first position and extending backward from the first position; and a metallic layer filling a part in the second region, and formed essentially of a second metallic material that has a higher melting temperature than a melting temperature of the first metallic material.
    Type: Grant
    Filed: March 25, 2013
    Date of Patent: October 28, 2014
    Assignee: TDK Corporation
    Inventors: Kosuke Tanaka, Susumu Aoki, Keita Kawamori, Hiroki Kawato
  • Patent number: 8861124
    Abstract: A heat-assisted magnetic recording (HAMR) transducer is coupled with a laser for providing energy and has an air-bearing surface (ABS) configured to reside in proximity to a media during use. The HAMR transducer includes a waveguide optically coupled with the laser and an optical power monitor optically coupled with the waveguide. The waveguide directs energy from the laser toward the media. The optical power monitor is optically coupled with the waveguide. The optical power monitor for captures a portion of the energy, converts the portion of the energy to heat and measures a local temperature proximate to the optical power monitor.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: October 14, 2014
    Assignee: Western Digital (Fremont), LLC
    Inventors: Marc A. Finot, Matthew R. Gibbons, William J. Kozlovsky, Hongxing Yuan
  • Patent number: 8861316
    Abstract: A write pole structure disclosed herein includes a write pole, a trailing shield, and a high magnetic moment (HMM) material layer on a surface of the trailing shield facing the write pole.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: October 14, 2014
    Assignee: Seagate Technology LLC
    Inventors: Huaqing Yin, Jianhua Xue, Venkateswara Rao Inturi, Mark Thomas Kief, Michael C. Kautzky
  • Patent number: 8861135
    Abstract: A thermally-assisted magnetic write head includes a waveguide, a magnetic pole, and a plasmon generator interposed between the waveguide and the magnetic pole. The magnetic pole includes a first surface exposed on an air bearing surface, a second surface facing the plasmon generator, and a third surface connecting the first surface and the second surface.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: October 14, 2014
    Assignee: TDK Corporation
    Inventor: Kenichi Takano
  • Patent number: 8854930
    Abstract: Techniques for improving the recording quality during heat assisted magnetic recording (HAMR) by monitoring the power of a source used to heat a storage medium are described. In one example, a source emits electromagnetic radiation. A waveguide transmits the electromagnetic radiation onto a surface of a magnetic media. A photoresistive material is proximately located to the waveguide. The resistance of the photoresistive material varies based on the intensity of electromagnetic radiation propagating through the waveguide. The power of the source is determined by measuring the resistance of the photoresitive material. The power of the source is adjusted based on the determined power.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: October 7, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Thomas William Clinton, Takuya Matsumoto, Shen Ren, Erhard Schreck, Barry Cushing Stipe
  • Patent number: 8848307
    Abstract: An apparatus includes a magnetic recording layer and a thermally active material adjacent to and/or embedded in the magnetic recording layer, wherein the thermally active material has a thermal property that changes when the temperature of the thermally active material changes, or undergoes a phase transition in a predetermined temperature range, to reduce a peak temperature or increase a thermal gradient of a heated portion of the magnetic recording layer.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: September 30, 2014
    Assignee: Seagate Technology LLC
    Inventors: Michael Allen Seigler, William Challener
  • Publication number: 20140285919
    Abstract: The thermally-assisted magnetic recording head includes: a magnetic pole having an end exposed on an air-bearing surface; a waveguide; a plasmon generator formed essentially of a first metallic material, and having a first region and a second region, the first region extending backward from the air-bearing surface to a first position, and the second region being coupled with the first region at the first position and extending backward from the first position; and a metallic layer filling a part in the second region, and formed essentially of a second metallic material that has a higher melting temperature than a melting temperature of the first metallic material.
    Type: Application
    Filed: March 25, 2013
    Publication date: September 25, 2014
    Applicant: TDK CORPORATION
    Inventors: Kosuke TANAKA, Susumu AOKI, Keita KAWAMORI, Hiroki KAWATO
  • Patent number: 8842505
    Abstract: According to one embodiment, a first magnetic head is used to record or reproduce data on or from the first disk surface and includes a first two-terminal element including a first positive terminal and a first negative terminal. A second magnetic head is used to record or reproduce data on or from the second disk surface and includes a second two-terminal element including a second positive terminal and a second negative terminal. A current control unit includes a first current terminal which is commonly connected to the first positive terminal and the second negative terminal and a second current terminal that is commonly connected to the first negative terminal and the second positive terminal and can switch a current polarity between the first current terminal and the second current terminal.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: September 23, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yuuichi Yamada