Patents by Inventor Devin Underwood

Devin Underwood 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: 20240412089
    Abstract: A device comprises a control circuit configured to control a plurality of quantum bits. The control circuit comprises a digital-to-analog converter circuit and switching circuitry coupled to an output of the digital-to-analog converter circuit. The switching circuitry is responsive to switch control signals to selectively connect the output of the digital-to-analog converter circuit to one or more of a plurality of signal paths to generate control signals to control the plurality of quantum bits.
    Type: Application
    Filed: June 6, 2023
    Publication date: December 12, 2024
    Inventors: Devin Underwood, Sudipto Chakraborty
  • Patent number: 11949439
    Abstract: Systems and techniques that facilitate mitigation of baseband pulse distortion via radiofrequency-to-baseband conversion are provided. In various embodiments, a system can comprise a qubit. In various aspects, the system can further comprise a signal generator that can produce a radiofrequency signal. In various instances, the system can further comprise a signal converter coupled between the qubit and the signal generator. In various cases, the signal converter can convert the radiofrequency signal into a baseband signal. In various aspects, such radiofrequency-to-baseband conversion can reduce a dispersion-induced distortion associated with driving the qubit.
    Type: Grant
    Filed: December 16, 2021
    Date of Patent: April 2, 2024
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Timothy Phung, Devin Underwood, Jiri Stehlik, David Zajac
  • Publication number: 20240095564
    Abstract: A quantum circuit device includes a qubit chip including a plurality of qubits and a plurality of flux tunable couplers. A plurality of fixed frequency qubits are arranged in in a lattice structure, wherein each pair of the plurality of fixed frequency qubits is coupled to one flux tunable coupler. A wiring layer is coupled to the qubit chip, and the wiring layer includes a loop constructed of a superconducting material that is inductively coupled to the flux tunable couplers. A flux bias line is constructed of a superconducting material that is different than the superconducting material of the loop, wherein the flux bias line is inductively coupled to both the loop and the flux tunable couplers.
    Type: Application
    Filed: September 15, 2022
    Publication date: March 21, 2024
    Inventors: Devin Underwood, Jiri Stehlik, Oliver Dial, David Lokken-Toyli
  • Publication number: 20240070506
    Abstract: One or more systems, devices, and/or methods of use provided herein relate to signal filters for scalable quantum computing architectures. According to one embodiment, a device can comprise a circuit board comprising a plurality of layers, wherein various ones of the plurality of layers comprises a different absorptive material, and a plurality of signal lines that pass through the circuit board, wherein a first layer of the circuit board is comprised of a first material that filters a first signal line that traverses through at least the first layer of the plurality of layers.
    Type: Application
    Filed: August 26, 2022
    Publication date: February 29, 2024
    Inventors: Devin Underwood, Timothy Phung, Muir Kumph
  • Publication number: 20230351232
    Abstract: Devices and/or computer-implemented methods to facilitate a quantum gate between qubits using a tunable coupler and a capacitor device are provided. According to an embodiment, a quantum coupler device can comprise a tunable coupler coupled between terminals of a same polarity of a first qubit and a second qubit, the tunable coupler configured to control a first coupling between the first qubit and the second qubit. The quantum coupler device can further comprise a capacitor device coupled to terminals of an opposite polarity of the first qubit and the second qubit, the capacitor device configured to provide a second coupling that is opposite in sign relative to the first coupling.
    Type: Application
    Filed: June 20, 2023
    Publication date: November 2, 2023
    Inventors: Jiri Stehlik, Devin Underwood, David Zajac, Matthias Steffen
  • Patent number: 11714142
    Abstract: Techniques for creating a low pass filter associated with a flux line are presented. A qubit device can comprise a first substrate and second substrate. A low pass filter, comprising at least one inductor and at least one capacitor can be formed, wherein respective components of or associated with the low pass filter can be formed on the first or second substrates, and wherein one or more bump bonds can extend between the substrates to connect respective components that are on respective substrates. The filter can receive an input signal via an input line and filter the signal to produce a filtered signal as output to a flux line that is in proximity to a coupler with SQUID loop and one or more flux-tunable qubits that are formed on one of the substrates. The filter can reduce electrical noise and Purcell decay associated with the flux line.
    Type: Grant
    Filed: December 11, 2020
    Date of Patent: August 1, 2023
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Timothy Phung, Jiri Stehlik, Devin Underwood
  • Publication number: 20230198555
    Abstract: Systems and techniques that facilitate mitigation of baseband pulse distortion via radiofrequency-to-baseband conversion are provided. In various embodiments, a system can comprise a qubit. In various aspects, the system can further comprise a signal generator that can produce a radiofrequency signal. In various instances, the system can further comprise a signal converter coupled between the qubit and the signal generator. In various cases, the signal converter can convert the radiofrequency signal into a baseband signal. In various aspects, such radiofrequency-to-baseband conversion can reduce a dispersion-induced distortion associated with driving the qubit.
    Type: Application
    Filed: December 16, 2021
    Publication date: June 22, 2023
    Inventors: Timothy Phung, Devin Underwood, Jiri Stehlik, David Zajac
  • Publication number: 20230170889
    Abstract: One or more systems, devices, methods of use and/or methods of fabrication provided herein relate to a quantum computing device that can operated to have 1st order insensitivity to flux noise. According to one embodiment, a device comprises a flux tunable qubit capacitively coupled to a flux tunable bus. According to another embodiment, a device comprises a flux tunable qubit capacitively coupled to a flux tunable bus, wherein the flux tunable bus is capacitively coupled a fixed frequency qubit.
    Type: Application
    Filed: November 30, 2021
    Publication date: June 1, 2023
    Inventors: Devin Underwood, Jiri Stehlik, David James Frank, Timothy Phung, David Zajac
  • Patent number: 11664570
    Abstract: A method of multiplexing control lines of a qubit array includes applying a qubit control signal to a single driveline. The qubit control signal is split on the single driveline between a first resonator and a second resonator. The first driveline is operative to control a first qubit, a second tunable qubit, a third qubit, and a fourth tunable qubit. The first qubit is coupled to the second tunable qubit by the first resonator. The third qubit is coupled to the fourth tunable qubit by the second resonator. A variation in amplitude of the qubit control signal is compensated by adjusting a frequency of the second tunable qubit and a frequency of the fourth tunable qubit.
    Type: Grant
    Filed: August 21, 2020
    Date of Patent: May 30, 2023
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Devin Underwood, Jiri Stehlik, David Zajac
  • Publication number: 20220187388
    Abstract: Techniques for creating a low pass filter associated with a flux line are presented. A qubit device can comprise a first substrate and second substrate. A low pass filter, comprising at least one inductor and at least one capacitor can be formed, wherein respective components of or associated with the low pass filter can be formed on the first or second substrates, and wherein one or more bump bonds can extend between the substrates to connect respective components that are on respective substrates. The filter can receive an input signal via an input line and filter the signal to produce a filtered signal as output to a flux line that is in proximity to a coupler with SQUID loop and one or more flux-tunable qubits that are formed on one of the substrates. The filter can reduce electrical noise and Purcell decay associated with the flux line.
    Type: Application
    Filed: December 11, 2020
    Publication date: June 16, 2022
    Inventors: Timothy Phung, Jiri Stehlik, Devin Underwood
  • Publication number: 20220059919
    Abstract: A method of multiplexing control lines of a qubit array includes applying a qubit control signal to a single driveline. The qubit control signal is split on the single driveline between a first resonator and a second resonator. The first driveline is operative to control a first qubit, a second tunable qubit, a third qubit, and a fourth tunable qubit. The first qubit is coupled to the second tunable qubit by the first resonator. The third qubit is coupled to the fourth tunable qubit by the second resonator. A variation in amplitude of the qubit control signal is compensated by adjusting a frequency of the second tunable qubit and a frequency of the fourth tunable qubit.
    Type: Application
    Filed: August 21, 2020
    Publication date: February 24, 2022
    Inventors: Devin Underwood, Jiri Stehlik, David Zajac