# US 12,015,397 B2 · High connectivity parametric gate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,015,397 B2 - Document ID: US12015397B2 - Status: Granted - Kind: B2 - Application number: 17/820,721 - Filed: 2022-08-18 - Published: 2024-02-22 - Granted: 2024-06-18 - Earliest claimed: 2022-08-18 - Assignees: International Business Machines Corporation - Applicants: International Business Machines Corporation - Inventors: Timothy Phung - Web page: https://patentgrep.com/patent/US12015397B2 ## CPC - G06N 10/20: Models of quantum computing, e.g. quantum circuits or universal quantum computers - H03K 17/92: by the use, as active elements, of superconductive devices - G06N 10/40: Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control - H10N 60/12: Josephson-effect devices - H10N 69/00: Integrated devices, or assemblies of multiple devices, comprising at least one superconducting element covered by group H10N60/00 - G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract One or more systems, devices, and/or methods of manufacture and/or use provided herein relate to a quantum computing process to achieve higher connectivity of qubits to more than nearest neighbors and/or to a plurality of nearest neighbors. A system can comprise a tunable first coupler coupled to a first qubit, a tunable second coupler coupled to a second qubit, and a junction coupling the first coupler and the second coupler being both parametrically drivable. The first coupler and the second coupler can comprise superconducting quantum interference devices or Josephson junctions. The junction can comprise a central hub or central node separately coupled to the first coupler and the second coupler. The first coupler and the second coupler can be configured to capacitively or inductively couple the first qubit and the second qubit to one another to perform a control-Z (CZ) gate or an iSWAP gate. ## Claims ### Claim 1 An electronic device comprising: a tunable first coupler coupled to a first qubit; a tunable second coupler coupled to a second qubit; and a junction coupling the first coupler and the second coupler, wherein the first coupler and the second coupler are parametrically drivable. ### Claim 2 (depends on 1) The electronic device of claim 1, wherein the first coupler and the second coupler comprise superconducting quantum interference devices or Josephson junctions. ### Claim 3 (depends on 1) The electronic device of claim 1, wherein the junction comprises a central hub or central node separately coupled to the first coupler and the second coupler. ### Claim 4 (depends on 3) The electronic device of claim 3, wherein the junction comprises a central hub, and wherein the central hub comprises a loop of series-coupled inductors. ### Claim 5 (depends on 1) The electronic device of claim 1, further comprising: a third coupler coupled to a third qubit, wherein the junction couples the first coupler, the second coupler and the third coupler, wherein the third coupler is parametrically drivable, wherein the junction is separately coupled to the first coupler, the second coupler and the third coupler. ### Claim 6 (depends on 1) The electronic device of claim 1, wherein the junction provides the only coupling between the first qubit and the second qubit. ### Claim 7 (depends on 1) The electronic device of claim 1, wherein the first coupler and the second coupler are configured to capacitively or inductively couple the first qubit and the second qubit to one another, and are configured to perform a controlled-Z (CZ) gate employing the first qubit and the second qubit. ### Claim 8 (depends on 1) The electronic device of claim 1, wherein the first coupler and the second coupler are configured to capacitively or inductively couple the first qubit and the second qubit to one another, and are configured to perform an iSWAP gate employing the first qubit and the second qubit. ### Claim 9 A method of performing a quantum gate operation, the method comprising: applying, by a system operatively coupled to a processor, a first bias and a first parametric drive to a first coupler coupled to a first qubit; applying, by the system, a second bias and a second parametric drive to a second coupler coupled to a second qubit and to the first coupler; and performing, by the system, a parametric gate operation employing the first qubit and the second qubit. ### Claim 10 (depends on 9) The method of claim 9, further comprising: applying, by the system, the first parametric drive and the second parametric drive at a respective frequency of a difference of respective frequencies of the first qubit and the second qubit. ### Claim 11 (depends on 10) The method of claim 10, further comprising: applying, by the system, the first parametric drive and the second parametric drive when the first qubit is in a respective excited state and the second qubit is in a respective excited state. ### Claim 12 (depends on 9) The method of claim 9, further comprising: applying, by the system, the first parametric drive and the second parametric drive at a respective frequency of a difference of respective frequencies of the first qubit and the second qubit plus or minus an anharmonicity of the first and second qubits. ### Claim 13 (depends on 12) The method of claim 12, further comprising: applying, by the system, the first parametric drive and the second parametric drive when one of the first qubit or the second qubit is in a respective excited state, and the other of the first qubit or the second qubit is in a respective ground state. ### Claim 14 (depends on 9) The method of claim 9, further comprising: inductively coupling, by the system, the first coupler and the second coupler by a pair of radio frequency superconducting quantum interference devices of the first coupler and the second coupler. ### Claim 15 (depends on 9) The method of claim 9, further comprising: capacitively coupling, by the system, the first coupler and the second coupler by a single coupling node. ### Claim 16 (depends on 9) The method of claim 9, further comprising: applying, by the system, a third bias and a third parametric drive to a third coupler coupled to a third qubit; applying, by the system, a fourth bias and a fourth parametric drive to a fourth coupler coupled to a fourth qubit; and performing, by the system, in parallel with the parametric gate operation, a second parametric gate operation employing the third qubit and the fourth qubit, wherein the first coupler, the second coupler, the third coupler and the fourth coupler are coupled to one another by a single junction. ### Claim 17 An electronic device comprising: a plurality of tunable couplers, comprising superconducting quantum interference devices, and separately coupled to respective qubits; and a junction coupling the plurality of tunable couplers by all-to-all coupling, wherein the first coupler and the second coupler are parametrically drivable. ### Claim 18 (depends on 17) The electronic device of claim 17, wherein the junction comprises a central hub, wherein the central hub comprises a loop of series-coupled inductors, and wherein the number of series-coupled inductors is equal to the number of tunable couplers of the plurality of tunable couplers. ### Claim 19 (depends on 17) The electronic device of claim 17, wherein the plurality of tunable couplers are configured to capacitively or inductively couple a pair of the respective qubits to one another, and are configured to perform a controlled-Z (CZ) gate or an iSWAP gate employing the pair of the respective qubits. ### Claim 20 (depends on 17) The electronic device of claim 17, wherein the plurality of tunable couplers and the junction are jointly configured to perform a first parametric gate operation employing a pair of tunable couplers of the plurality of tunable couplers, and to perform, in parallel with the first parametric gate operation, a second parametric gate operation employing a pair of different tunable couplers of the plurality of tunable couplers.