# US 2025/0148337 A1 · Arrangement and method for making a coupling to a qubit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0148337 A1 - Document ID: US20250148337A1 - Status: Published application - Kind: A1 - Application number: 18/836,930 - Filed: 2022-02-16 - Published: 2025-05-08 - Earliest claimed: 2022-02-16 - Assignees: IQM Finland Oy - Applicants: Iqm Finland Oy - Inventors: Hermanni HEIMONEN; Pasi LÄHTEENMÄKI - Web page: https://patentgrep.com/patent/US20250148337A1 ## CPC - 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 - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract An arrangement for making a coupling to a qubit comprises said qubit and another circuit element, which is to be controllably coupled to said qubit and decoupled therefrom. A network of resonators is provided between said qubit and said other circuit element. Said network of resonators comprises a plurality of resonators, comprising linear or nonlinear resonators or both. At least two of said plurality of resonators have an identical circuit topology but different frequency responses. ## Claims ### Claim 1 An arrangement for making a coupling to a qubit, comprising: said qubit, another circuit element, which is to be controllably coupled to said qubit and decoupled therefrom for performing quantum computing operations, and a network of resonators between said qubit and said other circuit element; wherein said network of resonators comprises a plurality of resonators, comprising linear or nonlinear resonators or both, and wherein at least two of said plurality of resonators have an identical circuit topology but different frequency responses. ### Claim 2 (depends on 1) The arrangement according to claim 1, wherein said other circuit element is a quantum circuit refrigerator. ### Claim 3 (depends on 1) The arrangement according to claim 1, wherein said other circuit element is another qubit. ### Claim 4 (depends on 1) The arrangement according to claim 1, wherein said network of resonators comprises said plurality of resonators coupled in series between said qubit and said other circuit element. ### Claim 5 (depends on 4) The arrangement according to claim 4, wherein there are at least six of said resonators coupled in series between said qubit and said other circuit element. ### Claim 6 (depends on 4) The arrangement according to claim 4, wherein each of said resonators comprises a capacitively shunted Josephson junction. ### Claim 7 (depends on 4) The arrangement according to claim 4, wherein each of said resonators comprises a qubit. ### Claim 8 (depends on 1) The arrangement according to claim 1, wherein said network of resonators comprises at least one serially coupled LC resonator as a part of the connection between said qubit and said other circuit element and at least one LC resonator between said connection and ground. ### Claim 9 (depends on 8) The arrangement according to claim 8, comprising three LC resonators between said connection and ground, of which one is coupled between a middle point of said serially coupled LC resonator and ground. ### Claim 10 (depends on 1) A quantum computing system, comprising a plurality of qubits, at least one of which constitutes a part of an arrangement according to claim 1. ### Claim 11 (depends on 10) The quantum computing system according to claim 10, wherein: said plurality of qubits form an array, and each qubit in said array constitutes a part of the arrangement, the qubits in said array constituting said other circuit elements to each other. ### Claim 12 (depends on 11) A quantum computing system according to claim 11, wherein: said qubits in said array are addressable through a grid addressing scheme that involves a grid of addressing lines in at least two distinct directions through said array, so that combinations of control signals through said grid addressing scheme are configured to selectably define, which qubits in said array become coupled together through said network of resonators. ### Claim 13 A method for making a coupling to a qubit, comprising: controllably coupling and decoupling said qubit with another circuit element for performing quantum computing operations, and conveying said controllable coupling through a network of resonators between said qubit and said other circuit element; wherein said network of resonators comprises a plurality of resonators, comprising linear or nonlinear resonators or both, and wherein at least two of said plurality of resonators have an identical circuit topology but different frequency responses. ### Claim 14 (depends on 13) The method according to claim 13, wherein said resonators are static resonators and said controllable coupling and decoupling are done by tuning the operating frequency of at least one of said qubit and said other circuit element. ### Claim 15 (depends on 13) The method according to claim 13, wherein among said plurality of resonators is at least one frequency-tunable resonator, and said controllable coupling and decoupling involve tuning the resonant frequency or frequencies of such at least one frequency-tunable resonator. ### Claim 16 (depends on 5) The arrangement according to claim 5, wherein each of said resonators comprises a capacitively shunted Josephson junction. ### Claim 17 (depends on 5) The arrangement according to claim 5, wherein each of said resonators comprises a qubit.