公开(公告)号：US11922276B2

公开(公告)日：2024-03-05

申请号：US17729999

申请日：2022-04-26

Applicant: Google LLC

Inventor： Rami Barends

IPC: G06N10/00 ,  G01R33/035 ,  H10N60/80

CPC classification number: G06N10/00 ,  G01R33/0354 ,  H10N60/805

Abstract: A device includes: a substrate; a superconducting quantum interference device (SQUID) including a superconductor trace arranged on an upper surface of the substrate and having at least one Josephson junction interrupting a path of the superconductor trace, in which the superconductor trace includes a first superconductor material that exhibits superconducting properties at or below a corresponding superconducting critical temperature; and a dielectric capping layer on an upper surface of the SQUID, in which the dielectric capping layer covers a majority of the superconductor trace of the SQUID, and the capping layer includes an opening through which a first region of the SQUID is exposed, the first region of the SQUID including a first Josephson junction.

公开(公告)号：US11562280B2

公开(公告)日：2023-01-24

申请号：US16636522

申请日：2017-08-09

Applicant: Google LLC

Inventor： John Martinis ,  Rami Barends ,  Austin Greig Fowler

IPC: G06N10/00 ,  H03K19/177

Abstract: Methods and systems for performing a surface code error detection cycle. In one aspect, a method includes initializing and applying Hadamard gates to multiple measurement qubits; performing entangling operations on a first set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a first direction; performing entangling operations on a second set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a second or third direction, the second and third direction being perpendicular to the first direction, the second direction being opposite to the third direction; performing entangling operations on a third set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a fourth direction, the fourth direction being opposite to the first direction; applying Hadamard gates to the measurement qubits; and measuring the measurement qubits.

公开(公告)号：US20220300846A1

公开(公告)日：2022-09-22

申请号：US17729999

申请日：2022-04-26

Applicant: Google LLC

Inventor： Rami Barends

IPC: G06N10/00 ,  G01R33/035 ,  H01L39/02

Abstract: A device includes: a substrate; a superconducting quantum interference device (SQUID) including a superconductor trace arranged on an upper surface of the substrate and having at least one Josephson junction interrupting a path of the superconductor trace, in which the superconductor trace includes a first superconductor material that exhibits superconducting properties at or below a corresponding superconducting critical temperature; and a dielectric capping layer on an upper surface of the SQUID, in which the dielectric capping layer covers a majority of the superconductor trace of the SQUID, and the capping layer includes an opening through which a first region of the SQUID is exposed, the first region of the SQUID including a first Josephson junction.

公开(公告)号：US20220246677A1

公开(公告)日：2022-08-04

申请号：US17610241

申请日：2019-05-10

Applicant: Google LLC

Inventor： Julian Shaw Kelly ,  Anthony Edward Megrant ,  Rami Barends ,  Charles Neill ,  Daniel Thomas Sank ,  Evan Jeffrey ,  Amit Vainsencher ,  Paul Klimov ,  Christopher Michael Quintana

IPC: H01L27/18 ,  G06N10/40 ,  H01L39/22

Abstract: A quantum computing device includes: a qubit; a single XYZ control line, in which the qubit and the single control line are configured and arranged such that, during operation of the quantum computing device, the single XYZ control line allows coupling of an XY qubit control flux bias, from the single XYZ control line to the qubit, over a first frequency range at a first predetermined effective coupling strength, and coupling of a Z qubit control flux bias, from the single XYZ control line to the qubit, over a second frequency range at a second predetermined effective coupling strength.

公开(公告)号：US11188849B2

公开(公告)日：2021-11-30

申请号：US17096524

申请日：2020-11-12

Applicant: Google LLC

Inventor： Rami Barends

IPC: G06N20/00 ,  G06N10/00 ,  F41J1/10 ,  F41J5/18 ,  F41J7/04 ,  F41J9/02 ,  H01L27/18 ,  H03K3/38 ,  A63F9/02

Abstract: Apparatus and methods for removing leakage from a qubit. In one aspect, an apparatus includes one or more qubits, wherein each qubit facilitates occupation of at least one of a plurality of qubit levels, the qubit levels including two computational levels and one or more non-computational levels that are each higher than the computational levels, wherein the qubit facilitates transitions between qubit levels associated with a corresponding transition frequency; a cavity, wherein the cavity defines a cavity frequency; one or more couplers coupling each qubit to the cavity; one or more couplers coupling the cavity to an environment external to the one or more qubits and the cavity; a frequency controller that controls the frequency of each qubit such that, for each qubit, the frequency of the qubit is adjusted relative to the cavity frequency such that a population of a non-computational level is transferred to the cavity.

公开(公告)号：US20210042654A1

公开(公告)日：2021-02-11

申请号：US17078846

申请日：2020-10-23

Applicant: Google LLC

Inventor： Rami Barends

IPC: G06N10/00 ,  G06F17/16

Abstract: Methods, systems, and apparatus for individual qubit excitation control with a global excitation drive. In one aspect, a method includes accessing a quantum system that comprises a plurality of qubits; a plurality of qubit frequency control lines, each qubit frequency control line corresponding to an individual qubit and controlling the frequency of the qubit; a driveline; a plurality of couplers, each coupler coupling a corresponding qubit to the driveline so that a plurality of qubits are coupled to the driveline; determining one or more qubits that require a rotation operation; for each qubit requiring a rotation operation: tuning the qubit frequency to the corresponding driveline frequency of the rotation operation; performing the rotation operation using a microwave pulse on the excitation drive; and tuning the qubit away from the driveline frequency of the rotation operation.

公开(公告)号：US20190383586A1

公开(公告)日：2019-12-19

申请号：US16555672

申请日：2019-08-29

Applicant: Google LLC

Inventor： Rami Barends

IPC: F41J7/04 ,  F41J9/02 ,  F41J5/18 ,  F41J1/10

Abstract: Apparatus and methods for removing leakage from a qubit. In one aspect, an apparatus includes one or more qubits, wherein each qubit facilitates occupation of at least one of a plurality of qubit levels, the qubit levels including two computational levels and one or more non-computational levels that are each higher than the computational levels, wherein the qubit facilitates transitions between qubit levels associated with a corresponding transition frequency; a cavity, wherein the cavity defines a cavity frequency; one or more couplers coupling each qubit to the cavity; one or more couplers coupling the cavity to an environment external to the one or more qubits and the cavity; a frequency controller that controls the frequency of each qubit such that, for each qubit, the frequency of the qubit is adjusted relative to the cavity frequency such that a population of a non-computational level is transferred to the cavity.

公开(公告)号：US20190332965A1

公开(公告)日：2019-10-31

申请号：US16474171

申请日：2017-12-08

Applicant: Google LLC

Inventor： Rami Barends

IPC: G06N10/00 ,  H01L39/02 ,  G01R33/035

Abstract: A device includes: a substrate; a superconducting quantum interference device (SQUID) including a superconductor trace arranged on an upper surface of the substrate and having at least one Josephson junction interrupting a path of the superconductor trace, in which the superconductor trace includes a first superconductor material that exhibits superconducting properties at or below a corresponding superconducting critical temperature; and a dielectric capping layer on an upper surface of the SQUID, in which the dielectric capping layer covers a majority of the superconductor trace of the SQUID, and the capping layer includes an opening through which a first region of the SQUID is exposed, the first region of the SQUID including a first Josephson junction.

公开(公告)号：US20240378473A1

公开(公告)日：2024-11-14

申请号：US18781756

申请日：2024-07-23

Applicant: Google LLC

Inventor： John Martinis ,  Rami Barends ,  Austin Greig Fowler

IPC: G06N10/00 ,  H03K19/177

Abstract: Methods and systems for performing a surface code error detection cycle. In one aspect, a method includes initializing and applying Hadamard gates to multiple measurement qubits; performing entangling operations on a first set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a first direction; performing entangling operations on a second set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a second or third direction, the second and third direction being perpendicular to the first direction, the second direction being opposite to the third direction; performing entangling operations on a third set of paired qubits, wherein each pair comprises a measurement qubit coupled to a neighboring data qubit in a fourth direction, the fourth direction being opposite to the first direction; applying Hadamard gates to the measurement qubits; and measuring the measurement qubits.

公开(公告)号：US12141661B2

公开(公告)日：2024-11-12

申请号：US18305152

申请日：2023-04-21

Applicant: Google LLC

Inventor： Kevin Chenghao Miao ,  Alexander Korotkov ,  Matthew James McEwen ,  Rami Barends

IPC: G06N10/70 ,  G06N10/40

Abstract: Methods, systems and apparatus for resetting a qubit. In one aspect, an apparatus includes a qubit, wherein the state of the qubit occupies a plurality of levels comprising two computational levels and one or more non-computational levels; a resonator that operates at a resonator frequency; control electronics that control a frequency of the qubit such that during a reset operation the qubit frequency is adjusted from a holding frequency that is lower than the resonator frequency to an idling frequency that is higher than the resonator frequency, and during the adjustment a first derivative of the qubit frequency at a first time is positive, at a second time that occurs after the first time is zero, and at a third time that occurs after the second time is positive, where the qubit frequency achieves the idling frequency at a fourth time that occurs after the third time.