Patents by Inventor Donald L. Miller

Donald L. Miller 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: 11145361
    Abstract: A bistable device allows supercurrent to flow when functioning in one regime, wherein magnetization directions of different magnetic layers are antiparallel, but restricts supercurrent when switched to function in a resistive regime, wherein the magnetization directions are parallel. In the first regime, the device acts as a Josephson junction, which allows it to be used in superconducting quantum interference devices (SQUIDs) and other circuits in which quantization of magnetic flux in a superconducting loop is desired. In the second, resistive regime, flux quantization is effectively eliminated in loops containing the device, and current is diverted to parallel superconducting components. The bistable device thereby acts as a superconducting switch, useful for a variety of circuit applications, including to steer current for memory or logic circuits, adjust logical circuit functionality at runtime, or to burn off stray flux during cooldown.
    Type: Grant
    Filed: November 30, 2020
    Date of Patent: October 12, 2021
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Eric C. Gingrich, Randall M. Burnett, Donald L. Miller
  • Patent number: 11120869
    Abstract: One example includes a memory cell system. The memory cell system includes a quantizing loop configured to conduct a quantizing current in a first direction corresponding to storage of a first state of a stored memory state of the memory cell system and to conduct the quantizing current in a second direction opposite the first direction corresponding to storage of a second state of the stored memory state of the memory cell system. The memory cell system also includes a bias element arranged in the quantizing loop and which is configured to provide a substantially constant flux bias of the quantizing loop in each of the first and second states of the stored memory state.
    Type: Grant
    Filed: September 15, 2020
    Date of Patent: September 14, 2021
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Ofer Naaman, Donald L. Miller, Henry Y Luo
  • Publication number: 20210110868
    Abstract: A bistable device allows supercurrent to flow when functioning in one regime, wherein magnetization directions of different magnetic layers are antiparallel, but restricts supercurrent when switched to function in a resistive regime, wherein the magnetization directions are parallel. In the first regime, the device acts as a Josephson junction, which allows it to be used in superconducting quantum interference devices (SQUIDs) and other circuits in which quantization of magnetic flux in a superconducting loop is desired. In the second, resistive regime, flux quantization is effectively eliminated in loops containing the device, and current is diverted to parallel superconducting components. The bistable device thereby acts as a superconducting switch, useful for a variety of circuit applications, including to steer current for memory or logic circuits, adjust logical circuit functionality at runtime, or to burn off stray flux during cooldown.
    Type: Application
    Filed: November 30, 2020
    Publication date: April 15, 2021
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: ERIC C. GINGRICH, RANDALL M. BURNETT, DONALD L. MILLER
  • Publication number: 20210005249
    Abstract: One example includes a memory cell system. The memory cell system includes a quantizing loop configured to conduct a quantizing current in a first direction corresponding to storage of a first state of a stored memory state of the memory cell system and to conduct the quantizing current in a second direction opposite the first direction corresponding to storage of a second state of the stored memory state of the memory cell system. The memory cell system also includes a bias element arranged in the quantizing loop and which is configured to provide a substantially constant flux bias of the quantizing loop in each of the first and second states of the stored memory state.
    Type: Application
    Filed: September 15, 2020
    Publication date: January 7, 2021
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: OFER NAAMAN, DONALD L. MILLER, HENRY Y LUO
  • Patent number: 10885974
    Abstract: A bistable device allows supercurrent to flow when functioning in one regime, wherein magnetization directions of different magnetic layers are antiparallel, but restricts supercurrent when switched to function in a resistive regime, wherein the magnetization directions are parallel. In the first regime, the device acts as a Josephson junction, which allows it to be used in superconducting quantum interference devices (SQUIDs) and other circuits in which quantization of magnetic flux in a superconducting loop is desired. In the second, resistive regime, flux quantization is effectively eliminated in loops containing the device, and current is diverted to parallel superconducting components. The bistable device thereby acts as a superconducting switch, useful for a variety of circuit applications, including to steer current for memory or logic circuits, adjust logical circuit functionality at runtime, or to burn off stray flux during cooldown.
    Type: Grant
    Filed: January 30, 2019
    Date of Patent: January 5, 2021
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Eric C. Gingrich, Randall M. Burnett, Donald L. Miller
  • Patent number: 10818346
    Abstract: One example includes a memory cell system that includes a quantizing loop that conducts a quantizing current in a first direction corresponding to a first stored memory state and to conduct the quantizing current in a second direction corresponding to a second stored memory state. The system also includes a bias element configured to provide a substantially constant flux bias of the quantizing loop in each of the first and second states of the stored memory state. The stored memory state can be read from the memory cell system in response to the substantially constant flux bias and a read current that is provided to the memory cell system. The system further includes a tunable energy element that is responsive to a write current that is provided to the memory cell system to change the state of the stored memory state between the first state and the second state.
    Type: Grant
    Filed: September 17, 2018
    Date of Patent: October 27, 2020
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Ofer Naaman, Donald L. Miller, Henry Y Luo
  • Publication number: 20200243133
    Abstract: A bistable device allows supercurrent to flow when functioning in one regime, wherein magnetization directions of different magnetic layers are antiparallel, but restricts supercurrent when switched to function in a resistive regime, wherein the magnetization directions are parallel. In the first regime, the device acts as a Josephson junction, which allows it to be used in superconducting quantum interference devices (SQUIDs) and other circuits in which quantization of magnetic flux in a superconducting loop is desired. In the second, resistive regime, flux quantization is effectively eliminated in loops containing the device, and current is diverted to parallel superconducting components. The bistable device thereby acts as a superconducting switch, useful for a variety of circuit applications, including to steer current for memory or logic circuits, adjust logical circuit functionality at runtime, or to burn off stray flux during cooldown.
    Type: Application
    Filed: January 30, 2019
    Publication date: July 30, 2020
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: ERIC C. GINGRICH, RANDALL M. BURNETT, DONALD L. MILLER
  • Patent number: 10622977
    Abstract: One example includes a superconducting bidirectional current driver. The current driver includes a first direction superconducting latch that is activated in response to a first activation signal to provide a first current path of an input current through a bidirectional current load in a first direction. The current driver also includes a second direction superconducting latch that is activated in response to a second activation signal to provide a second current path of the input current through the bidirectional current load in a second direction opposite the first direction.
    Type: Grant
    Filed: October 2, 2018
    Date of Patent: April 14, 2020
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Ofer Naaman, Donald L. Miller, Randall M. Burnett
  • Publication number: 20200090738
    Abstract: One example includes a memory cell system that includes a quantizing loop that conducts a quantizing current in a first direction corresponding to a first stored memory state and to conduct the quantizing current in a second direction corresponding to a second stored memory state. The system also includes a bias element configured to provide a substantially constant flux bias of the quantizing loop in each of the first and second states of the stored memory state. The stored memory state can be read from the memory cell system in response to the substantially constant flux bias and a read current that is provided to the memory cell system. The system further includes a tunable energy element that is responsive to a write current that is provided to the memory cell system to change the state of the stored memory state between the first state and the second state.
    Type: Application
    Filed: September 17, 2018
    Publication date: March 19, 2020
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: OFER NAAMAN, DONALD L. MILLER, HENRY Y. LUO
  • Patent number: 10389336
    Abstract: One embodiment describes a Josephson transmission line (JTL) system. The system includes a plurality of JTL stages that are arranged in series. The system also includes a clock transformer comprising a primary inductor configured to propagate an AC clock signal and a secondary inductor arranged in a series loop with at least two of the plurality of JTL stages. The clock transformer can be configured to propagate a single flux quantum (SFQ) pulse to set a respective one of the plurality of JTL stages in response to a first phase of the AC clock signal and to reset the respective one of the plurality of JTL stages in response to a second phase of the AC clock signal that is opposite the first phase.
    Type: Grant
    Filed: September 7, 2018
    Date of Patent: August 20, 2019
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Donald L. Miller, Ofer Naaman
  • Patent number: 10367483
    Abstract: One embodiment describes a Josephson current source system comprising a flux-shuttle loop that is inductively coupled with an AC input signal. The flux-shuttle loop includes a plurality of stages each comprising at least one Josephson junction. The plurality of stages can be spaced about the flux shuttle loop. Each of a plurality of pairs of the plurality of stages are configured to concurrently trigger in a sequence via the respective at least one Josephson junction in response to the AC input signal and to provide a respective pair of single-flux quantum (SFQ) pulses that move sequentially and continuously through each stage of the plurality of stages around the flux-shuttle loop via each of the at least one Josephson junction of each of the respective stages that results in a DC output current being provided through an output inductor.
    Type: Grant
    Filed: December 20, 2018
    Date of Patent: July 30, 2019
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Quentin P. Herr, Anna Y. Herr, Donald L. Miller, Christopher S. Bulla, Theodore R. Blank
  • Patent number: 10355677
    Abstract: One example includes a current driver system. The system includes a current source configured to provide a source current to a transition node. The system also includes a Josephson latch comprising at least one Josephson junction stage. The at least one Josephson junction stage can be configured to conduct the source current from the transition node as a current-clamped bias current in a deactivated state of the Josephson latch. The Josephson latch can be configured to activate in response to the bias current and a trigger pulse to switch the at least one Josephson junction stage to a voltage state to conduct at least a portion of the source current from the transition node as an output current to a load in response to activation of the Josephson latch.
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: July 16, 2019
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Donald L. Miller, Quentin P. Herr
  • Patent number: 10204677
    Abstract: A memory system including an array of memory cells may include a set of word-lines, and a set of return word-lines coupled to the memory cells in the array of memory cells. The memory system may further include a set of bit-lines coupled to the memory cells. Each of the memory cells may include a memory storage element including a readout superconducting quantum interference device (SQUID), and a magnetic Josephson Junction (MJJ), and where the memory storage element may further include a differential transformer coupled in series with the MJJ such that in response to a bit-line current applied to at least one of the set of the bit-lines and a word-line current applied to at least one of the set of word-lines, the differential transformer is configured to induce a flux in the at least one readout SQUID.
    Type: Grant
    Filed: March 16, 2018
    Date of Patent: February 12, 2019
    Assignee: Microsoft Technology Licensing, LLC
    Inventors: Henry Y. Luo, Quentin P. Herr, Randall M. Burnett, Donald L. Miller
  • Publication number: 20190036515
    Abstract: One example includes a superconducting bidirectional current driver. The current driver includes a first direction superconducting latch that is activated in response to a first activation signal to provide a first current path of an input current through a bidirectional current load in a first direction. The current driver also includes a second direction superconducting latch that is activated in response to a second activation signal to provide a second current path of the input current through the bidirectional current load in a second direction opposite the first direction.
    Type: Application
    Filed: October 2, 2018
    Publication date: January 31, 2019
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: OFER NAAMAN, DONALD L. MILLER, RANDALL M. BURNETT
  • Patent number: 10166584
    Abstract: Control of self-excited third octave vibration in a metal rolling mill can be achieved by adjusting the tension of the metal strip as it enters a stand. Self-excited third octave vibration can be detected and/or measured by one or more sensors. A high-speed tension adjustor can rapidly adjust the entry tension of the metal strip (e.g., as the metal strip enters a mill stand) to compensate for the detected self-excited third octave vibration. High-speed tension adjustors can include any combination of hydraulic or piezoelectric actuators coupled to the center roll of a bridle roll to rapidly raise or lower the roll and thus induce rapid tension adjustments in the strip. Other high-speed tension adjustors can be used.
    Type: Grant
    Filed: July 15, 2015
    Date of Patent: January 1, 2019
    Assignee: Novelis Inc.
    Inventors: Rodger Brown, Matthew Seibert, Donald L. Miller, Matthew Fairlie, David Gaensbauer
  • Patent number: 10122350
    Abstract: One embodiment describes a Josephson transmission line (JTL) system. The system includes a plurality of JTL stages that are arranged in series. The system also includes a clock transformer comprising a primary inductor configured to propagate an AC clock signal and a secondary inductor arranged in a series loop with at least two of the plurality of JTL stages. The clock transformer can be configured to propagate a single flux quantum (SFQ) pulse to set a respective one of the plurality of JTL stages in response to a first phase of the AC clock signal and to reset the respective one of the plurality of JTL stages in response to a second phase of the AC clock signal that is opposite the first phase.
    Type: Grant
    Filed: November 17, 2015
    Date of Patent: November 6, 2018
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Donald L. Miller, Ofer Naaman
  • Patent number: 10122352
    Abstract: One example includes a current driver system. The system includes a current source configured to provide a source current to a transition node. The system also includes a Josephson latch comprising at least one Josephson junction stage. The at least one Josephson junction stage can be configured to conduct the source current from the transition node as a current-clamped bias current in a deactivated state of the Josephson latch. The Josephson latch can be configured to activate in response to the bias current and a trigger pulse to switch the at least one Josephson junction stage to a voltage state to conduct at least a portion of the source current from the transition node as an output current to a load in response to activation of the Josephson latch.
    Type: Grant
    Filed: May 7, 2018
    Date of Patent: November 6, 2018
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Donald L. Miller, Quentin P. Herr
  • Patent number: 10122351
    Abstract: One example includes a superconducting bidirectional current driver. The current driver includes a first direction superconducting latch that is activated in response to a first activation signal and a second direction superconducting latch that is activated in response to a second activation signal. The second direction superconducting latch is activated to provide a first current path of an input current through the first direction superconducting latch and through a bidirectional current load in a first direction. The first direction superconducting latch is activated to provide a second current path of the input current through the second direction superconducting latch and through the bidirectional current load in a second direction opposite the first direction.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: November 6, 2018
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Ofer Naaman, Donald L. Miller, Randall M. Burnett
  • Publication number: 20170141769
    Abstract: One embodiment describes a Josephson transmission line (JTL) system. The system includes a plurality of JTL stages that are arranged in series. The system also includes a clock transformer comprising a primary inductor configured to propagate an AC clock signal and a secondary inductor arranged in a series loop with at least two of the plurality of JTL stages. The clock transformer can be configured to propagate a single flux quantum (SFQ) pulse to set a respective one of the plurality of JTL stages in response to a first phase of the AC clock signal and to reset the respective one of the plurality of JTL stages in response to a second phase of the AC clock signal that is opposite the first phase.
    Type: Application
    Filed: November 17, 2015
    Publication date: May 18, 2017
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: DONALD L. MILLER, OFER NAAMAN
  • Patent number: 9646682
    Abstract: One embodiment describes a reciprocal quantum logic (RQL) sense amplifier system. The system includes an input stage configured to amplify a sense current received at an input. The system also includes a detection stage configured to trigger at least one detection Josephson junction (JJ) in response to the amplified sense current and based on a clock signal to generate a single flux quantum (SFQ) pulse. The system further includes a Josephson transmission line (JTL) stage configured to propagate the SFQ pulse to an output of the RQL sense amplifier system based on at least one output JJ and to generate a negative SFQ pulse to reset the at least one detection JJ and the at least one output JJ based on the clock signal.
    Type: Grant
    Filed: May 27, 2016
    Date of Patent: May 9, 2017
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Donald L. Miller, Quentin P. Herr, Anna Y. Herr