Patents by Inventor Robert Hempstead

Robert Hempstead 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).

  • Patent number: 7541105
    Abstract: Epitaxial ferroelectric and magnetic recording structures having graded lattice matching layers are disclosed. A single crystal material such as Si may be used as a substrate material upon which the graded lattice matching layers are deposited. The lattice matching layers may comprise metals and metal alloys, or may comprise oxides doped with selected elements or deposited under different oxygen pressures. A recording layer, such as ferroelectric lead zirconium titanate or a magnetic Fe/Pt multilayer structure, is deposited on the graded lattice matching layers.
    Type: Grant
    Filed: September 25, 2006
    Date of Patent: June 2, 2009
    Assignee: Seagate Technology LLC
    Inventors: Thomas Francis Ambrose, Joachim Walter Ahner, Kai-Chieh Chang, Maissarath Nassirou, Robert Hempstead, Mark Lutwyche
  • Publication number: 20080075980
    Abstract: Epitaxial ferroelectric and magnetic recording structures having graded lattice matching layers are disclosed. A single crystal material such as Si may be used as a substrate material upon which the graded lattice matching layers are deposited. The lattice matching layers may comprise metals and metal alloys, or may comprise oxides doped with selected elements or deposited under different oxygen pressures. A recording layer, such as ferroelectric lead zirconium titanate or a magnetic Fe/Pt multilayer structure, is deposited on the graded lattice matching layers.
    Type: Application
    Filed: September 25, 2006
    Publication date: March 27, 2008
    Inventors: Thomas Francis Ambrose, Joachim Walter Ahner, Kai-Chieh Chang, Maissarath Nassirou, Robert Hempstead, Mark Lutwyche
  • Publication number: 20050094315
    Abstract: An information storage system includes a transducer having a loop of ferromagnetic material with pole tips separated by an nonferromagnetic gap located adjacent to a medium such as a rigid disk. During writing the separation between the pole tips and the media layer of the disk is a small fraction of the gap separation. Due to the small separation between the pole tips and the media layer, the magnetic field generated by the transducer and felt by the media has a larger perpendicular than longitudinal component, favoring perpendicular recording over longitudinal recording. The media may have an easy axis of magnetization oriented substantially along the perpendicular direction, so that perpendicular data storage is energetically favored. The transducer may also include a magnetoresistive sensor for reading magnetic information from the disk.
    Type: Application
    Filed: October 20, 2004
    Publication date: May 5, 2005
    Inventors: Alexander Payne, William Cain, Michael Devillier, Harold Hamilton, Robert Hempstead, Darren Imai, Dimitre Latev, David Roberts