Patents by Inventor Kin Chung Fong

Kin Chung Fong 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).

  • Publication number: 20180337324
    Abstract: A photon detector including a graphene-insulating-superconducting junction configured as a temperature sensor. Photons are absorbed by the graphene sheet of the graphene-insulating-superconducting junction, each absorbed photon causing a temporary increase in the temperature of the graphene sheet, and a corresponding change in the differential impedance of the graphene-insulating-superconducting junction. The graphene-insulating-superconducting junction is part of a resonant circuit connected as a shunt load between a radio frequency input transmission line and a radio frequency output transmission line. The transmission S-parameter from input to output is affected by the impedance of the resonant circuit which in turn is affected by the differential impedance of the graphene-insulating-superconducting junction, and therefore by the temperature of the graphene sheet.
    Type: Application
    Filed: May 18, 2018
    Publication date: November 22, 2018
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Patent number: 10024721
    Abstract: A bolometer. In one embodiment a graphene sheet is configured to absorb electromagnetic waves. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Electromagnetic power in the evanescent electromagnetic waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of electromagnetic wave power absorbed by the graphene sheet.
    Type: Grant
    Filed: January 12, 2018
    Date of Patent: July 17, 2018
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventor: Kin Chung Fong
  • Publication number: 20180136047
    Abstract: A bolometer. In one embodiment a graphene sheet is configured to absorb electromagnetic waves. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Electromagnetic power in the evanescent electromagnetic waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of electromagnetic wave power absorbed by the graphene sheet.
    Type: Application
    Filed: January 12, 2018
    Publication date: May 17, 2018
    Inventor: Kin Chung Fong
  • Patent number: 9945728
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. The graphene sheet has two contacts connected to an amplifier, a power detector, and a pulse detector. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet, which increases the Johnson noise generated at the contacts. The Johnson noise is amplified and the absorption of a photon is detected by the power detector and pulse detector.
    Type: Grant
    Filed: July 7, 2015
    Date of Patent: April 17, 2018
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventor: Kin Chung Fong
  • Patent number: 9933310
    Abstract: An infrared bolometer. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Infrared electromagnetic power in the evanescent waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of infrared power propagating in the waveguide.
    Type: Grant
    Filed: July 8, 2015
    Date of Patent: April 3, 2018
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventor: Kin Chung Fong
  • Patent number: 9869592
    Abstract: A bolometer. In one embodiment a graphene sheet is configured to absorb electromagnetic waves. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Electromagnetic power in the evanescent electromagnetic waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of electromagnetic wave power absorbed by the graphene sheet.
    Type: Grant
    Filed: July 18, 2017
    Date of Patent: January 16, 2018
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventor: Kin Chung Fong
  • Publication number: 20170317220
    Abstract: A bolometer. In one embodiment a graphene sheet is configured to absorb electromagnetic waves. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Electromagnetic power in the evanescent electromagnetic waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of electromagnetic wave power absorbed by the graphene sheet.
    Type: Application
    Filed: July 18, 2017
    Publication date: November 2, 2017
    Inventor: Kin Chung Fong
  • Patent number: 9799817
    Abstract: A detector for detecting single photons of infrared radiation or longer wavelength electromagnetic radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In other embodiments a transmission line or antenna is coupled to the graphene sheet and guides longer-wavelength photons to the graphene sheet. A photon absorbed by the graphene sheet heats the graphene sheet. Part of the graphene sheet is part of the Josephson junction as the weak link, and a constant bias current is driven through the Josephson junction; an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: October 24, 2017
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Patent number: 9761782
    Abstract: A detector for detecting single photons of infrared radiation or longer wavelength electromagnetic radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In other embodiments a transmission line or antenna is coupled to the graphene sheet and guides longer-wavelength photons to the graphene sheet. A photon absorbed by the graphene sheet heats the graphene sheet. Part of the graphene sheet is part of the Josephson junction as the weak link, and a constant bias current is driven through the Josephson junction; an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: September 12, 2017
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Patent number: 9666743
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In some embodiments the waveguide is omitted and infrared light propagating in free space illuminates the graphene sheet directly. A photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: August 19, 2016
    Date of Patent: May 30, 2017
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Publication number: 20170092834
    Abstract: A detector for detecting single photons of infrared radiation or longer wavelength electromagnetic radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In other embodiments a transmission line or antenna is coupled to the graphene sheet and guides longer-wavelength photons to the graphene sheet. A photon absorbed by the graphene sheet heats the graphene sheet. Part of the graphene sheet is part of the Josephson junction as the weak link, and a constant bias current is driven through the Josephson junction; an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Application
    Filed: September 28, 2016
    Publication date: March 30, 2017
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Patent number: 9577176
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: February 21, 2017
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Publication number: 20170038260
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. The graphene sheet has two contacts connected to an amplifier, a power detector, and a pulse detector. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet, which increases the Johnson noise generated at the contacts. The Johnson noise is amplified and the absorption of a photon is detected by the power detector and pulse detector.
    Type: Application
    Filed: July 7, 2015
    Publication date: February 9, 2017
    Inventor: Kin Chung Fong
  • Patent number: 9548436
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: January 17, 2017
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Publication number: 20160370232
    Abstract: An infrared bolometer. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. The graphene sheet has two contacts connected to an amplifier, and a power detector connected to the amplifier. Infrared electromagnetic power in the evanescent waves is absorbed in the graphene sheet, heating the graphene sheet. The power of Johnson noise generated at the contacts is proportional to the temperature of the graphene sheet. The Johnson noise is amplified and the power in the Johnson noise is used as a measure of the temperature of the graphene sheet, and of the amount of infrared power propagating in the waveguide.
    Type: Application
    Filed: July 8, 2015
    Publication date: December 22, 2016
    Inventor: Kin Chung Fong
  • Publication number: 20160372622
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In some embodiments the waveguide is omitted and infrared light propagating in free space illuminates the graphene sheet directly. A photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Application
    Filed: August 19, 2016
    Publication date: December 22, 2016
    Inventors: Kin Chung Fong, Thomas A. Ohki
  • Patent number: 9502630
    Abstract: A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: November 22, 2016
    Assignee: RAYTHEON BBN TECHNOLOGIES CORP.
    Inventors: Kin Chung Fong, Thomas A. Ohki