Patents by Inventor Frederick C. Wellstood

Frederick C. Wellstood 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: 10176431
    Abstract: A dissipative device has a planar configuration with one or more resistor elements formed on an insulating substrate. Conductors are formed on the insulating substrate and are coupled to the resistor element(s) to transmit signals to/from the resistor element(s). The geometry of and materials for the dissipative device allow the conductors to act as heat sinks, which conduct heat generated in the resistor element(s) to the substrate (and on to a coupled housing) and cool hot electrons generated by the resistor element(s) via electron-phonon coupling. The dissipative device can be used in cooling a signal to a qubit, a cavity system of a quantum superconducting qubit, or any other cryogenic device sensitive to thermal noise.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: January 8, 2019
    Assignees: University of Maryland, College Park, The United States of America, as represented by the Director, National Security Agency
    Inventors: Jen-Hao Yeh, Benjamin S. Palmer, Frederick C. Wellstood, Jay LeFebvre
  • Publication number: 20170257074
    Abstract: A dissipative device has a planar configuration with one or more resistor elements formed on an insulating substrate. Conductors are formed on the insulating substrate and are coupled to the resistor element(s) to transmit signals to/from the resistor element(s). The geometry of and materials for the dissipative device allow the conductors to act as heat sinks, which conduct heat generated in the resistor element(s) to the substrate (and on to a coupled housing) and cool hot electrons generated by the resistor element(s) via electron-phonon coupling. The dissipative device can be used in cooling a signal to a qubit, a cavity system of a quantum superconducting qubit, or any other cryogenic device sensitive to thermal noise.
    Type: Application
    Filed: March 2, 2017
    Publication date: September 7, 2017
    Applicants: University of Maryland, College Park, The United States of America as represented by the Director, National Security Agency
    Inventors: Jen-Hao Yeh, Benjamin S. Palmer, Frederick C. Wellstood, Jay LeFebvre
  • Patent number: 7268542
    Abstract: A scanning SQUID microscope is set forth to provide improved output imaging. The SQUID microscope includes a vertically adjustable housing adapted to securely retain a SQUID loop or sensor. A scanning stage of the SQUID microscope is adapted to support a sample while moving the sample along a predetermined path to selectively position predetermined portions of the sample in close proximity to the SQUID loop or sensor to permit the loop or sensor to detect predetermined magnetic field information provided by the predetermined portions of the sample. A position control processor coupled to the scanning stage is operative to receive and process the predetermined magnetic field information to provide corresponding position noise information. Criteria are also presented for determining the expected level of position noise under given experimental conditions.
    Type: Grant
    Filed: February 16, 2005
    Date of Patent: September 11, 2007
    Assignee: United States of America as represented by the Secretary of the Air Force
    Inventors: Frederick C. Wellstood, Su-Young Lee, John Matthews
  • Patent number: 6809533
    Abstract: A near-field scanning microwave microscope images the permittivity and dielectric tunability of bulk and thin film dielectric samples on a length scale of about 1 micron or less. The microscope is sensitive to the linear permittivity, as well as to non-linear dielectric terms, which can be measured as a function of an applied electric field. A versatile finite element model is used for the system, which allows quantitive results to e obtained. The technique is non-destructive and has broadband (0.1-50 GHz) capability.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: October 26, 2004
    Assignee: University of Maryland, College Park
    Inventors: Steven Mark Anlage, David E. Steinhauer, Constantine P. Vlahacos, Frederick C. Wellstood
  • Patent number: 6516281
    Abstract: A system, method, and computer program product are provided for scanning objects such as computer chips. A near-field scanning Single Electron Transistor (SET) is used to detect features of the object. In particular, the SET detects variations in an electric field surrounding or emanating from the object. The variation in the field may be associated with an irregularity in the object, such as an open in the circuitry of a chip. In the case of a chip or a multi-chip module, a voltage is applied to the line containing the suspected open. If an actual open is present, the open will be manifested in an irregularity in the electric field associated with the line. The SET detects the irregularity in the field. For the SET to operate, a sufficiently cold operating temperature is maintained for the SET. A very low (cryogenic) temperature allows the use of a larger, more sensitive SET. Scanning SETs are known in the literature, but in such systems the object to be scanned must also be at cryogenic temperatures.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: February 4, 2003
    Assignee: University of Maryland
    Inventors: Frederick C. Wellstood, Matthew Edward Kenyon, Christopher J. Lobb
  • Patent number: 5491411
    Abstract: A magnetic flux microscope that measures the magnetic field about a sample surface. The apparatus uses a thin-film superconducting quantum interference device (SQUID) as the scanning device. Magnetic shielding is provided about the SQUID and is held stationary relative to the SQUID. The apparatus and method provides a very high magnetic image of the sample with a very high spatial and field resolution.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: February 13, 1996
    Assignee: University of Maryland
    Inventors: Frederick C. Wellstood, Anna Mathai, Dian Song, Randall C. Black
  • Patent number: 5291035
    Abstract: A microelectronic component comprising a crossover is provided comprising a substrate, a first high T.sub.c superconductor thin film, a second insulating thin film comprising SrTiO.sub.3 ; and a third high T.sub.c superconducting film which has strips which crossover one or more areas of the first superconductor film. An in situ method for depositing all three films on a substrate is provided which does not require annealing steps and which can be opened to the atmosphere between depositions.
    Type: Grant
    Filed: March 10, 1993
    Date of Patent: March 1, 1994
    Assignee: The Regents of the University of California
    Inventors: Frederick C. Wellstood, John J. Kingston, John Clarke
  • Patent number: 5256636
    Abstract: A microelectronic component comprising a crossover is provided comprising a substrate, a first high T.sub.c superconductor thin film, a second insulating thin film comprising SrTiO.sub.3 ; and a third high T.sub.c superconducting film which has strips which crossover one or more areas of the first superconductor film. An insitu method for depositing all three films on a substrate is provided which does not require annealing steps. The photolithographic process is used to separately pattern the high T.sub.c superconductor thin films.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: October 26, 1993
    Assignee: The Regents of the University of Calif.
    Inventors: Frederick C. Wellstood, John J. Kingston, John Clarke