# US 12,217,882 B2 · Methods and apparatuses for cross-talk mitigation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,217,882 B2 - Document ID: US12217882B2 - Status: Granted - Kind: B2 - Application number: 17/867,414 - Filed: 2022-07-18 - Published: 2023-02-02 - Granted: 2025-02-04 - Earliest claimed: 2021-07-16 - Assignees: IonQ, Inc. - Applicants: IonQ, Inc. - Inventors: Michael Lurie Goldman; Jonathan Albert Mizrahi; Jeremy Matthew Sage - Web page: https://patentgrep.com/patent/US12217882B2 ## CPC - G21K 1/20: for confining charged particles or handling confined charged particles, e.g. ion traps - G06N 10/40: Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control - G06N 10/70: Quantum error correction, detection or prevention, e.g. surface codes or magic state distillation - G21K: HANDLING OF PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES - G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS ## Abstract Aspects of the present disclosure may include a method and/or a system for identifying an ion chain having a plurality of trapped ions, selecting at least two non-consecutive trapped ions in the ion chain for implementing a qubit, applying at least a first Raman beam to shuttle at least one neighbor ion of the at least two non-consecutive trapped ions from a ground state to a metastable state, and applying at least a second Raman beam to one or more of the at least two non-consecutive trapped ions, after shuttling the at least one neighbor ion to the metastable state, to transition from a first manifold to a second manifold. ## Claims ### Claim 1 A method for operating a quantum computer system, comprising: identifying an ion chain having a plurality of trapped ions; selecting at least two non-consecutive trapped ions in the ion chain for implementing a qubit; applying at least a first Raman beam to shuttle at least one neighbor of the at least two non-consecutive trapped ions from a ground state to a metastable state; and applying at least a second Raman beam to one or more of the at least two non-consecutive trapped ions after shuttling the at least one neighbor to the metastable state. ### Claim 2 (depends on 1) The method of claim 1, further comprising, prior to applying the at least first Raman beam and the at least second Raman beam: applying each of a plurality of Raman beams to each corresponding trapped ion of the plurality of trapped ions; and measuring optical cross-talk associated with neighboring trapped ions in response to applying each of the plurality of Raman beams to each of the corresponding trapped ion. ### Claim 3 (depends on 2) The method of claim 2, further comprising: selecting a first portion of the plurality of trapped ions, wherein first optical cross-talk of the first portion of the plurality of trapped ions is lower than second optical cross-talk of a second portion of the plurality of trapped ions. ### Claim 4 (depends on 3) The method of claim 3, wherein the first portion of the plurality of trapped ions includes the at least two non-consecutive trapped ions. ### Claim 5 (depends on 1) The method of claim 1, wherein applying the at least a first Raman beam comprises applying a composite pulse sequence. ### Claim 6 (depends on 1) The method of claim 1, wherein the plurality of trapped ions includes a plurality of dual-space, single-species (DSSS) trapped-ions. ### Claim 7 A non-transitory computer readable medium having instructions stored therein that, when executed by one or more processors of a quantum information processing (QIP) system, cause the one or more processors to: identify an ion chain having a plurality of trapped ions; select at least two non-consecutive trapped ions in the ion chain for implementing a qubit; cause a first light source to apply at least a first Raman beam to shuttle at least one neighbor of the at least two non-consecutive trapped ions from a ground state to a metastable state; and cause a second light source to apply at least a second Raman beam to one or more of the at least two non-consecutive trapped ions after shuttling the at least one neighbor to the metastable state. ### Claim 8 (depends on 7) The non-transitory computer readable medium of claim 7, further comprises instructions for: causing a third light source to apply each of a plurality of Raman beams to each corresponding trapped ion of the plurality of trapped ions; and measuring optical cross-talk associated with neighboring trapped ions in response to applying each of the plurality of Raman beams to each of the corresponding trapped ion. ### Claim 9 (depends on 8) The non-transitory computer readable medium of claim 8, further comprising instructions for: selecting a first portion of the plurality of trapped ions, wherein first optical cross-talk of the first portion of the plurality of trapped ions is lower than second optical cross-talk of a second portion of the plurality of trapped ions. ### Claim 10 (depends on 9) The non-transitory computer readable medium of claim 9, wherein the first portion of the plurality of trapped ions includes the at least two non-consecutive trapped ions. ### Claim 11 (depends on 7) The non-transitory computer readable medium of claim 7, wherein the instructions for causing the first light source to apply the at least a first Raman beam comprises instructions for causing the first light source to apply a composite pulse sequence. ### Claim 12 (depends on 7) The non-transitory computer readable medium of claim 7, wherein the plurality of trapped ions includes a plurality of dual-space, single-species (DSSS) trapped-ions. ### Claim 13 A quantum information processing (QIP) system, comprising: a controller configured to: identify an ion chain having a plurality of trapped ions; select at least two non-consecutive trapped ions in the ion chain for implementing a qubit; a first light source configured to apply at least a first Raman beam to shuttle at least one neighbor of the at least two non-consecutive trapped ions from a ground state to a metastable state; and a second light source configured to apply at least a second Raman beam to one or more of the at least two non-consecutive trapped ions after shuttling the at least one neighbor to the metastable state. ### Claim 14 (depends on 13) The QIP system of claim 13, further comprising: a third light source configured to apply each of a plurality of Raman beams to each corresponding trapped ion of the plurality of trapped ions; and wherein the controller is further configured to measure optical cross-talk associated with neighboring trapped ions in response to applying each of the plurality of Raman beams to each of the corresponding trapped ion. ### Claim 15 (depends on 14) The QIP system of claim 14, wherein the controller is further configured to select a first portion of the plurality of trapped ions, wherein first optical cross-talk of the first portion of the plurality of trapped ions is lower than second optical cross-talk of a second portion of the plurality of trapped ions. ### Claim 16 (depends on 15) The QIP system of claim 15, wherein the first portion of the plurality of trapped ions includes the at least two non-consecutive trapped ions. ### Claim 17 (depends on 13) The QIP system of claim 13, wherein the first light source is further configured to apply a composite pulse sequence. ### Claim 18 (depends on 13) The QIP system of claim 13, wherein the plurality of trapped ions includes a plurality of dual-space, single-species (DSSS) trapped-ions.