# US 12,008,437 B2 · Method and apparatus for qubit error detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,008,437 B2 - Document ID: US12008437B2 - Status: Granted - Kind: B2 - Application number: 17/434,163 - Filed: 2020-02-13 - Published: 2022-06-02 - Granted: 2024-06-11 - Earliest claimed: 2019-02-27 - Assignees: Forschungszentrum Julich GmbH - Applicants: Forschungszentrum Jülich GmbH - Inventors: Veit Langrock; David Divincenzo - Web page: https://patentgrep.com/patent/US12008437B2 ## CPC - G06N 10/70: Quantum error correction, detection or prevention, e.g. surface codes or magic state distillation - G06N 10/40: Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control - G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS ## Abstract The invention relates to a method and an apparatus for detecting a state of a data qubit by means of a parity qubit, wherein both the data qubit and the parity qubit can be moved by a moving means, wherein the distance between the data qubit and the parity qubit is so large that the parity qubit cannot query the state of the data qubit, wherein the distance between the data qubit and the parity qubit is reduced by moving the data qubit along a first path and the parity qubit along a second path until the state of the data qubit can be queried by the parity qubit, characterized in that the first path is longer than the second path and/or that the speed of movement of the parity qubit is greater than the speed of movement of the data qubit. ## Claims ### Claim 1 A method for detecting a faulty state of a data qubit using a parity qubit, wherein at least the parity qubit can be moved by a movement device, wherein a distance between the data qubit and the parity qubit is so large that the parity qubit cannot be entangled with the data qubit, wherein the distance between the data qubit and the parity qubit is reduced by moving the data qubit along a first path and the parity qubit along a second path until the data qubit can be entangled with the parity qubit, characterized in that the second path is longer than the first path and/or in that a speed of movement of the parity qubit is greater than a speed of movement of the data qubit. ### Claim 2 (depends on 1) The method of claim 1, wherein the parity qubit is in a measurable state before it is moved to one or more data qubits for entangling. ### Claim 3 (depends on 1) The method of claim 1 wherein the parity qubit is moved between two data qubits. ### Claim 4 (depends on 1) The method of claim 1 wherein after moving between two data qubits, the parity qubit is moved between two further data qubits. ### Claim 5 (depends on 1) The method of claim 1 wherein the parity qubit is moved away from data qubits after moving between two data qubits and the state of the parity qubit is measured. ### Claim 6 (depends on 1) The method of claim 1, wherein a plurality of parity qubits are moved between data qubits at the same time. ### Claim 7 (depends on 1) The method of claim 1, wherein a row of parity qubits are moved between two rows of data qubits. ### Claim 8 (depends on 1) The method of claim 1, wherein a row of parity qubits are moved away from two rows of data qubits and subsequently, the parity qubits are moved from the moved-out row of parity qubits to measuring stations. ### Claim 9 (depends on 1) The method of claim 1, wherein a qubit comprises at least one electron with a spin ½ or −½. ### Claim 10 (depends on 1) The method of claim 1, wherein a transport device generates an electric field and a qubit is moved by the electric field. ### Claim 11 An apparatus for performing a method for detecting a faulty state of a data qubit using a parity qubit, comprising data qubits and parity qubits, wherein a movement device is provided, with which the data qubits and the parity qubits can be moved, wherein a distance between the data qubit and the parity qubit can be so large that the parity qubit cannot be entangled with the data qubit, wherein the distance between the data qubit and the parity qubit can be reduced by moving the data qubit along a first path and the parity qubit along a second path until the data qubit can be entangled with the parity qubit, characterized in that the first path is longer than the second path and/or that a speed of movement of the parity qubit can be greater than a speed of movement of the data qubit. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the parity qubit is in a measurable state and in particular in a singlet state or a triplet state. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the parity qubit can be moved between two data qubits. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the apparatus is configured such that after moving between two data qubits, the parity qubit is moved between two further data qubits at a slow speed. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the parity qubit can be moved away from data qubits after moving between two data qubits and the state of the moved-away parity qubit can be measured. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein a plurality of parity qubits can be moved between data qubits at the same time. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein a row of parity qubits can be moved between two rows of data qubits. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein a row of parity qubits can be moved away from two rows of data qubits and subsequently, the parity qubits can be moved from the moved-out row of parity qubits to one or more measuring stations of the apparatus. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein the parity qubits comprises two electrons and the parity qubit is in a singlet state or a triplet state. ### Claim 20 (depends on 11) The apparatus of claim 11, wherein a transport device can generate an electric field and a qubit can be moved by the electric field.