Abstract: A write head for writing information bits to magnetic storage media includes a first write pole for producing a first magnetic field in a first direction and a second write pole for producing a second magnetic field such that the combined field from the two poles lies either substantially along the first direction or in a second direction that is substantially orthogonal to the first direction. The second write pole includes a free layer having magnetization controlled by spin transfer torque, and a first spacer positioned between the free layer and the first write pole. The write head can further include a pinned layer and a second spacer positioned between the pinned layer and the free layer. A disc drive that includes the write head and a method of writing to magnetic storage media that utilizes the write head are also included.
Type:
Grant
Filed:
May 21, 2002
Date of Patent:
August 31, 2004
Assignee:
Seagate Technology LLC
Inventors:
Mark William Covington, Thomas McLendon Crawford, Gregory John Parker, Petrus Antonius Van der Heijden
Abstract: An apparatus for providing environmental control, secondary power and emergency power for an aircraft, comprises a cooling turbine coupled to a first electromechanical machine rotor, and including an input for receiving compressed air or ram air, and an output for discharging cooled air or exhaust air; a compressor coupled to a second electromechanical machine rotor, and including an input for receiving engine bleed air or ambient air, and an output for discharging compressed air; means for magnetically coupling the first and second rotors; a power turbine coupled to the compressor; a heat exchanger connected between the compressor output and the cooling turbine input; and a control unit for controlling the magnetic coupling between the first and second rotors.
Abstract: A perpendicular magnetic recording medium includes a hard magnetic recording layer and a soft magnetic underlayer adjacent the hard magnetic recording layer. The soft magnetic underlayer includes first and second ferromagnetically coupled multilayer structures and a coupling layer positioned between the first and second multilayer structures for antiferromagnetically coupling the first and second multilayer structures. A magnetic disc drive storage system incorporating such a perpendicular magnetic recording medium and a method of making such a perpendicular magnetic recording medium are also included.
Type:
Grant
Filed:
April 4, 2002
Date of Patent:
August 17, 2004
Assignee:
Seagate Technology LLC
Inventors:
Isabel G. Trindade, Sharat Batra, Dieter K. Weller, Yukiko Kubota, Kurt W. Wierman, James K. Howard, Ganping Ju
Abstract: The present invention provides for the enhancement of the storage capacity of a data disk drive while reducing optical path optics, electronics and/or the mass and complexity of associated read/write heads. The system utilizes light transmitted by optical elements to servo track a data disk and to heat the data disk during reading and writing of data, and magnetic elements for actual reading and writing.
Type:
Grant
Filed:
March 29, 1999
Date of Patent:
August 10, 2004
Assignee:
Seagate Technology LLC
Inventors:
Karl A. Belser, Terry McDaniel, Edward C. Gage, James Durnin, Lori G. Swanson, Christina L. Hutchinson
Abstract: An endovascular stent graft is provided for use in treating abdominal aortic aneurysms. The endovascular stent has a tapered section which allows it to accommodate markedly large aortas such as the abdominal aorta and still connects to standard modular aortic stent grafts. Methods of utilizing the stent to treat abdominal aortic aneurysms and distal iliac aneurysms are also provided.
Type:
Grant
Filed:
January 2, 2001
Date of Patent:
August 10, 2004
Inventors:
Michael H. Wholey, Mark H. Wholey, Boulos Toursarkissian
Abstract: A perpendicular recording head for use with magnetic recording media includes a main pole having a concave tip. The concave tip focuses the magnetic flux from the main pole onto a smaller area of the magnetic recording medium than a conventional main pole when the main pole is at its flying height from the magnetic recording medium. Although the most preferred perpendicular recording head includes a concave cavity having an elliptical profile when viewed from the side, any substantially concave cavity may be used advantageously.
Type:
Grant
Filed:
September 19, 2000
Date of Patent:
August 3, 2004
Assignee:
Seagate Technology LLC
Inventors:
Sakhrat Khizroev, Dmitri Litvinov, Mark H. Kryder
Abstract: A perpendicular magnetic recording head includes a laminated main write pole and a return pole magnetically coupled to the main write pole. The main write pole includes a first magnetic layer having a high saturation magnetization, a second magnetic layer having a high saturation magnetization, and a non-magnetic interlayer positioned between the first magnetic layer and the second magnetic layer. The first and second magnetic layers may comprise, for example, FexCoy, wherein 40≦x≦90 and 10≦y≦60.
Abstract: The present invention provides a recording medium having a solid lubricating layer that has increased thermal stability over traditional solid lubricants. The lubricating layer includes amorphous fluorinated carbon doped with a thermally stabilizing dopant, such as N or SiO2. In one embodiment, a method of lubricating the recording medium by plasma-enhanced chemical vapor deposition is also provided.
Abstract: A read head for use with magnetic recording media having a plurality of magnetic tracks includes a read sensor, first and second magnetic lead shields for improving track resolution, and first and second magnetic shields for improving linear resolution. The read sensor is formed on a side wall of one of the first and second magnetic lead shields using a technique such as ion beam deposition for enhanced film growth rate on the side wall. A magnetic disc drive storage system incorporating the read head and a method of making the read head are also included.
Abstract: The present invention provides a hard disk drive laser assisted magnetic recording system including a semiconductor laser and magnetic write coil integrally formed into a slider. The slider preferably includes a perpendicular magnetic recording section adjacent a laser section. The laser section may form an air bearing surface of the slider. During recording operations, laser radiation from the laser section heats a region of the magnetic recording media in order to reduce its coercivity.
Type:
Grant
Filed:
September 13, 2000
Date of Patent:
July 13, 2004
Assignee:
Seagate Technology LLC
Inventors:
Edward Charles Gage, George Robert Gray, Lori Grace Swanson, Ronald Evan Gerber
Abstract: A spin valve read element for use with, for example, magnetic recording media, includes a permanent magnet as one of the multilayers that make up the spin valve. The spin valve may also include a pinned ferromagnetic layer, an antiferromagnetic coupling inducing layer, a reference ferromagnetic layer, an electroconductive layer, and/or a free ferromagnetic layer. Epitaxy breaking layers may also be advantageously positioned within the spin valve. The multilayers of the spin valve may be constructed as a current perpendicular to the plane or a current parallel to the plane type spin valve.
Type:
Grant
Filed:
October 15, 2002
Date of Patent:
June 22, 2004
Assignee:
Seagate Technology LLC
Inventors:
Michael A. Seigler, Paul E. Anderson, Alexander M. Shukh
Abstract: Magnetic films comprising iridium, manganese and nitrogen (IrMnN) are disclosed. Multi-layer structures including ferromagnetic layers deposited on the IrMnN films are also disclosed. The IrMnN films have a (200) texture and may act as seed layers and/or exchange biasing layers for the ferromagnetic layers deposited thereon. The multi-layer structures are useful in applications such as read sensors for magnetic recording heads and soft magnetic underlayers for perpendicular magnetic recording media.
Abstract: A read head for perpendicular magnetic recording that reduces side reading. The read head includes a read element and a magnetic shield spaced apart from the read element. The magnetic shield at least partially surrounds the read element at an air-bearing surface of the read element. The ratio of an air-bearing surface area of the magnetic shield to an air-bearing surface area of the read element is from about 1:1 to about 40:1.
Type:
Grant
Filed:
December 20, 2001
Date of Patent:
May 18, 2004
Assignee:
Seagate Technology LLC
Inventors:
Sakhrat Khizroev, Dmitri Litvinov, Roy Gustafson, Nisha Shukla
Abstract: A method is provided for transmitting a composite digital audio broadcast signal having an analog portion and a digital portion to mitigate intermittent interruptions in the reception of said digital audio broadcast signal. The method comprises the steps of arranging symbols representative of the digital portion of the digital audio broadcast signal into a plurality of audio frames, producing a plurality of modem frames, each of the modem frames including a group of the audio frames, and adding a frame synchronization signal to each of the modem frames. The modem frames are then transmitted along with the analog portion of the digital audio broadcast signal, with the analog portion being delayed by a time delay corresponding to an integral number of the modem frames. The invention also encompasses radio receivers and transmitters which process signals according to the above methods.
Abstract: A read head, particularly suitable for a magnetic disc storage system, includes a read sensor having an air-bearing surface and an opposing top surface. The read head also includes a permanent magnet positioned adjacent the top surface of the read sensor for generating a magnetic bias field in the read sensor. The permanent magnet has a magnetization in a direction other than normal to the air-bearing surface of the read sensor.
Type:
Grant
Filed:
October 2, 2001
Date of Patent:
April 20, 2004
Assignee:
Seagate Technology LLC
Inventors:
Michael Allen Seigler, Gregory John Parker, Petrus Antonius Van der Heijden
Abstract: A method for transmission of compressed data for a digital audio broadcasting system comprises the steps of producing digital information representative of an audio signal; estimating the number of bits to be allocated to the digital information in a modem frame; encoding the digital information within the estimated number of bits to produce encoded data; removing selected bits from the encoded data; adding bits corresponding to digital messages to the encoded information to form a composite modem frame; formatting the composite modem frame bits to produce formatted composite modem frame bits; and transmitting the formatted composite modem frame bits. The invention also encompasses transmitters that perform the method.
Type:
Grant
Filed:
August 24, 1999
Date of Patent:
April 13, 2004
Assignee:
iBiquity Digital Corporation
Inventors:
Brian William Kroeger, Stephen Douglas Mattson
Abstract: A recording head for use with magnetic storage medium applies a magnetic field at a 90-degree angle to the orientation of the magnetizations within the individual domain of the storage medium. This magnetic field results in rotation of the magnetization to approximately 90-degrees from its initial and its final orientation. From this position, a second magnetic field is capable of orienting the magnetization in the desired direction to record the desired bit. A simplified manufacturing process, wherein both of the opposing write poles and their connecting yoke are formed as a single layer during a single deposition or plating process, may be used to manufacture such a recording head.
Abstract: A method for making a magnetic sensor for a disk drive read head, the method comprising the steps of depositing a magnetoresistive stack on a surface of a first layer of material, depositing a resist layer on a first portion of the magnetoresistive stack, removing a second portion of the magnetoresistive stack not covered by the resist layer, depositing a layer of additional material on the magnetoresistive stack, the resist material, and the surface of the first layer, removing the additional material from sidewalls of the resist material, and using a lift-off process to remove the resist material. Magnetic sensors made by the above process are also included.
Type:
Grant
Filed:
July 26, 2001
Date of Patent:
March 30, 2004
Assignee:
Seagate Technology LLC
Inventors:
Michael Allen Seigler, Andrew Robert Eckert
Abstract: A recording head for use in conjunction with a magnetic storage medium, comprises a waveguide for providing a path for transmitting radiant energy, a near-field coupling structure positioned in the waveguide and including a plurality of arms, each having a planar section and a bent section, wherein the planar sections are substantially parallel to a surface of the magnetic storage medium, and the bent sections extend toward the magnetic storage medium and are separated to form a gap adjacent to an air bearing surface, and applying a magnetic write field to sections of the magnetic recording medium heated by the radiant energy. A disc drive including the recording head and a method of recording data using the recording head are also provided.