Patents by Inventor Steven A. Hawkins

Steven A. Hawkins 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: 10297706
    Abstract: A photoconductive switch is disclosed having a substrate, an electrode formed on the substrate, and a dielectric formed adjacent to the substrate and the electrode. The dielectric, the electrode and the substrate each have a portion cooperatively defining an interface area. The interface area of the dielectric has a doping making the interface area of the dielectric electrically conductive to suppress a charge collection at the interface area when the photoconductive switch is electrically energized through an input signal irradiating the electrode. In one embodiment the electrode may have a curvilinear or spherical shape, and the substrate may have a boundary edge surface which extends normal to the surface of the electrode, and with the dielectric having an edge surface that matches the contour of the substrate edge surface.
    Type: Grant
    Filed: June 2, 2017
    Date of Patent: May 21, 2019
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: Steven A. Hawkins, George J. Caporaso
  • Patent number: 10181544
    Abstract: Methods, systems, and devices are disclosed for photoconductive switch package configurations. In some aspects, a photoconductive switch package includes of a wide bandgap photoconductive material (e.g., GaN, ZnO, diamond, AlN, SiC, BN, etc.), a source for energetic photons (e.g., a laser), a mechanism to couple the laser into the switch, and a mechanism for high voltage to enter and leave the switch package. In some implementations, the disclosed photoconductive switch packages can be configured as a three terminal device, e.g., similar to transistors, with one of the terminals being laser input or the voltage input to the laser system.
    Type: Grant
    Filed: July 7, 2016
    Date of Patent: January 15, 2019
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: Scott D. Nelson, George J. Caporaso, Steven A. Hawkins, Hoang T. Nguyen, Stephen Sampayan, Li-Fang Wang
  • Publication number: 20180351025
    Abstract: A photoconductive switch is disclosed having a substrate, an electrode formed on the substrate, and a dielectric formed adjacent to the substrate and the electrode. The dielectric, the electrode and the substrate each have a portion cooperatively defining an interface area. The interface area of the dielectric has a doping making the interface area of the dielectric electrically conductive to suppress a charge collection at the interface area when the photoconductive switch is electrically energized through an input signal irradiating the electrode. In one embodiment the electrode may have a curvilinear or spherical shape, and the substrate may have a boundary edge surface which extends normal to the surface of the electrode, and with the dielectric having an edge surface that matches the contour of the substrate edge surface.
    Type: Application
    Filed: June 2, 2017
    Publication date: December 6, 2018
    Inventors: Steven A. Hawkins, George J. Caporaso
  • Publication number: 20180013028
    Abstract: Methods, systems, and devices are disclosed for photoconductive switch package configurations. In some aspects, a photoconductive switch package includes of a wide bandgap photoconductive material (e.g., GaN, ZnO, diamond, AlN, SiC, BN, etc.), a source for energetic photons (e.g., a laser), a mechanism to couple the laser into the switch, and a mechanism for high voltage to enter and leave the switch package. In some implementations, the disclosed photoconductive switch packages can be configured as a three terminal device, e.g., similar to transistors, with one of the terminals being laser input or the voltage input to the laser system.
    Type: Application
    Filed: July 7, 2016
    Publication date: January 11, 2018
    Inventors: Scott D. Nelson, George J. Caporaso, Steven A. Hawkins, Hoang T. Nguyen, Stephen Sampayan, Li-Fang Wang
  • Patent number: 9072156
    Abstract: The devices, systems and techniques disclosed here can be used to reduce undesired effects by magnetic field induced eddy currents based on a diamagnetic composite material structure including diamagnetic composite sheets that are separated from one another to provide a high impedance composite material structure. In some implementations, each diamagnetic composite sheet includes patterned conductor layers are separated by a dielectric material and each patterned conductor layer includes voids and conductor areas. The voids in the patterned conductor layers of each diamagnetic composite sheet are arranged to be displaced in position from one patterned conductor layer to an adjacent patterned conductor layer while conductor areas of the patterned conductor layers collectively form a contiguous conductor structure in each diamagnetic composite sheet to prevent penetration by a magnetic field.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: June 30, 2015
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: George J. Caporaso, Brian R. Poole, Steven A. Hawkins
  • Patent number: 9025919
    Abstract: A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces metalized with first metallic layers formed thereon, and encapsulated with a dielectric encapsulation material such as for example epoxy. The first metallic layers are exposed through the encapsulation via encapsulation concavities which have a known contour profile, such as a Rogowski edge profile. Second metallic layers are then formed to line the concavities and come in contact with the first metal layer, to form profiled and metalized encapsulation concavities which mitigate enhancement points at the edges of electrodes matingly seated in the concavities. One or more optical waveguides may also be bonded to the substrate for coupling light into the photo-conductive wafer, with the encapsulation also encapsulating the waveguides.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: May 5, 2015
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: James S. Sullivan, David M. Sanders, Steven A. Hawkins, Stephen A. Sampayan
  • Publication number: 20140265940
    Abstract: The devices, systems and techniques disclosed here can be used to reduce undesired effects by magnetic field induced eddy currents based on a diamagnetic composite material structure including diamagnetic composite sheets that are separated from one another to provide a high impedance composite material structure. In some implementations, each diamagnetic composite sheet includes patterned conductor layers are separated by a dielectric material and each patterned conductor layer includes voids and conductor areas. The voids in the patterned conductor layers of each diamagnetic composite sheet are arranged to be displaced in position from one patterned conductor layer to an adjacent patterned conductor layer while conductor areas of the patterned conductor layers collectively form a contiguous conductor structure in each diamagnetic composite sheet to prevent penetration by a magnetic field.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: George J. Caporaso, Brian R. Poole, Steven A. Hawkins
  • Patent number: 8655125
    Abstract: A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces, and at least one light-input surface. First metallic layers are formed on the electrode-interface surfaces, and one or more optical waveguides having input and output ends are bonded to the substrate so that the output end of each waveguide is bonded to a corresponding one of the light-input surfaces of the photo-conductive substrate. This forms a waveguide-substrate interface for coupling light into the photo-conductive wafer. A dielectric material such as epoxy is then used to encapsulate the photo-conductive substrate and optical waveguide so that only the metallic layers and the input end of the optical waveguide are exposed. Second metallic layers are then formed on the first metallic layers so that the waveguide-substrate interface is positioned under the second metallic layers.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: February 18, 2014
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: James S. Sullivan, David M. Sanders, Steven A. Hawkins, Stephen E. Sampayan
  • Patent number: 8575868
    Abstract: A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a “virtual” traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: November 5, 2013
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: George James Caporaso, Yu-Jiuan Chen, Scott Nelson, Jim Sullivan, Steven A. Hawkins
  • Patent number: 8258632
    Abstract: An improved photoconductive switch having a SiC or other wide band gap substrate material with opposing contoured profile cavities which have a contoured profile selected from one of Rogowski, Bruce, Chang, Harrison, and Ernst profiles, and two electrodes with matching contoured-profile convex interface surfaces.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: September 4, 2012
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: James S. Sullivan, Steven A. Hawkins
  • Publication number: 20120082411
    Abstract: A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces, and at least one light-input surface. First metallic layers are formed on the electrode-interface surfaces, and one or more optical waveguides having input and output ends are bonded to the substrate so that the output end of each waveguide is bonded to a corresponding one of the light-input surfaces of the photo-conductive substrate. This forms a waveguide-substrate interface for coupling light into the photo-conductive wafer. A dielectric material such as epoxy is then used to encapsulate the photo-conductive substrate and optical waveguide so that only the metallic layers and the input end of the optical waveguide are exposed. Second metallic layers are then formed on the first metallic layers so that the waveguide-substrate interface is positioned under the second metallic layers.
    Type: Application
    Filed: June 28, 2011
    Publication date: April 5, 2012
    Applicant: Lawrence Livermore National Security, LLC
    Inventors: James S. Sullivan, David M. Sanders, Steven A. Hawkins, Stephen A. Sampayan
  • Publication number: 20110297841
    Abstract: A charged particle focusing and deflection apparatus and system utilizing one or more (i.e. stacked) ring-shaped electrodes which are contorted or deformed to shape a multipole electric field and thereby effect multipole electric focusing and deflection. In particular the ring-shaped electrodes may be used in a high gradient insulator of a particle accelerator, such as a dielectric wall accelerator (DWA).
    Type: Application
    Filed: June 2, 2011
    Publication date: December 8, 2011
    Inventors: George J. Caporaso, Yu-Jiuan Chen, Steven A. Hawkins
  • Publication number: 20110101891
    Abstract: A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a “virtual” traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.
    Type: Application
    Filed: April 16, 2010
    Publication date: May 5, 2011
    Inventors: George James Caporaso, Yu-Jiuan Chen, Scott Nelson, Jim Sullivan, Steven A. Hawkins
  • Patent number: 7710051
    Abstract: A compact accelerator system having an integrated particle generator-linear accelerator with a compact, small-scale construction capable of producing an energetic (˜70-250 MeV) proton beam or other nuclei and transporting the beam direction to a medical therapy patient without the need for bending magnets or other hardware often required for remote beam transport. The integrated particle generator-accelerator is actuable as a unitary body on a support structure to enable scanning of a particle beam by direction actuation of the particle generator-accelerator.
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: May 4, 2010
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: George J. Caporaso, Yu-Jiuan Chen, Steven A. Hawkins, Stephen E. Sampayan, Arthur C. Paul
  • Publication number: 20100078198
    Abstract: A high gradient multilayer vacuum insulator (HGI) with increased resistance to vacuum arcing to improve electrical strength. In an exemplary embodiment, the HGI includes a plurality of conductive and dielectric layers stacked in alternating arrangement so that the edges of the layers together form a vacuum-insulator interface and the stack has an overall length LS. The dielectric layers each have a thickness I that is less than It I t = ( E M E BD ) 2 ? L S where It is the transitional dielectric layer thickness below which failure of the vacuum insulator is by vacuum arcing, EBD is the breakdown field required to initiate vacuum arcing across one of said dielectric layers, and EM is the breakdown field required to initiate surface flashover across a monolithic dielectric material of length LS.
    Type: Application
    Filed: August 7, 2009
    Publication date: April 1, 2010
    Inventors: John Richardson Harris, David M. Sandes, Steven A. Hawkins, Steven Falabella
  • Publication number: 20100060207
    Abstract: A compact accelerator system having an integrated particle generator-linear accelerator with a compact, small-scale construction capable of producing an energetic (˜70-250 MeV) proton beam or other nuclei and transporting the beam direction to a medical therapy patient without the need for bending magnets or other hardware often required for remote beam transport. The integrated particle generator-accelerator is actuable as a unitary body on a support structure to enable scanning of a particle beam by direction actuation of the particle generator-accelerator.
    Type: Application
    Filed: October 24, 2006
    Publication date: March 11, 2010
    Applicant: The Regents of the University of California
    Inventors: George J. Caporaso, Yu-Jiuan Chen, Steven A. Hawkins, Stephen E. Sampayan
  • Publication number: 20100032580
    Abstract: A compact accelerator system having an integrated particle generator-linear accelerator with a compact, small-scale construction capable of producing an energetic (˜70-250 MeV) proton beam or other nuclei and transporting the beam direction to a medical therapy patient without the need for bending magnets or other hardware often required for remote beam transport. The integrated particle generator-accelerator is actuable as a unitary body on a support structure to enable scanning of a particle beam by direction actuation of the particle generator-accelerator.
    Type: Application
    Filed: July 30, 2009
    Publication date: February 11, 2010
    Inventors: George J. Caporaso, Yu-Jiuan Chen, Steven A. Hawkins, Stephen E. Sampayan