Always-On Quantum Error Tracking with Continuous Parity Measurements
We investigate quantum error correction using continuous parity measurements to correct bit-flip errors with the three-qubit code. Continuous monitoring of errors brings the benefit of a continuous stream of information, which facilitates passive error tracking in real time. It reduces overhead from...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften
2020-11-01
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| Series: | Quantum |
| Online Access: | https://quantum-journal.org/papers/q-2020-11-04-358/pdf/ |
| _version_ | 1819052724972421120 |
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| author | Razieh Mohseninia Jing Yang Irfan Siddiqi Andrew N. Jordan Justin Dressel |
| author_facet | Razieh Mohseninia Jing Yang Irfan Siddiqi Andrew N. Jordan Justin Dressel |
| author_sort | Razieh Mohseninia |
| collection | DOAJ |
| description | We investigate quantum error correction using continuous parity measurements to correct bit-flip errors with the three-qubit code. Continuous monitoring of errors brings the benefit of a continuous stream of information, which facilitates passive error tracking in real time. It reduces overhead from the standard gate-based approach that periodically entangles and measures additional ancilla qubits. However, the noisy analog signals from continuous parity measurements mandate more complicated signal processing to interpret syndromes accurately. We analyze the performance of several practical filtering methods for continuous error correction and demonstrate that they are viable alternatives to the standard ancilla-based approach. As an optimal filter, we discuss an unnormalized (linear) Bayesian filter, with improved computational efficiency compared to the related Wonham filter introduced by Mabuchi [New J. Phys. 11, 105044 (2009)]. We compare this optimal continuous filter to two practical variations of the simplest periodic boxcar-averaging-and-thresholding filter, targeting real-time hardware implementations with low-latency circuitry. As variations, we introduce a non-Markovian ``half-boxcar'' filter and a Markovian filter with a second adjustable threshold; these filters eliminate the dominant source of error in the boxcar filter, and compare favorably to the optimal filter. For each filter, we derive analytic results for the decay in average fidelity and verify them with numerical simulations. |
| first_indexed | 2024-12-21T12:24:23Z |
| format | Article |
| id | doaj.art-203b0ad0766f4f1aaf08c9d65f5b3994 |
| institution | Directory Open Access Journal |
| issn | 2521-327X |
| language | English |
| last_indexed | 2024-12-21T12:24:23Z |
| publishDate | 2020-11-01 |
| publisher | Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften |
| record_format | Article |
| series | Quantum |
| spelling | doaj.art-203b0ad0766f4f1aaf08c9d65f5b39942022-12-21T19:04:13ZengVerein zur Förderung des Open Access Publizierens in den QuantenwissenschaftenQuantum2521-327X2020-11-01435810.22331/q-2020-11-04-35810.22331/q-2020-11-04-358Always-On Quantum Error Tracking with Continuous Parity MeasurementsRazieh MohseniniaJing YangIrfan SiddiqiAndrew N. JordanJustin DresselWe investigate quantum error correction using continuous parity measurements to correct bit-flip errors with the three-qubit code. Continuous monitoring of errors brings the benefit of a continuous stream of information, which facilitates passive error tracking in real time. It reduces overhead from the standard gate-based approach that periodically entangles and measures additional ancilla qubits. However, the noisy analog signals from continuous parity measurements mandate more complicated signal processing to interpret syndromes accurately. We analyze the performance of several practical filtering methods for continuous error correction and demonstrate that they are viable alternatives to the standard ancilla-based approach. As an optimal filter, we discuss an unnormalized (linear) Bayesian filter, with improved computational efficiency compared to the related Wonham filter introduced by Mabuchi [New J. Phys. 11, 105044 (2009)]. We compare this optimal continuous filter to two practical variations of the simplest periodic boxcar-averaging-and-thresholding filter, targeting real-time hardware implementations with low-latency circuitry. As variations, we introduce a non-Markovian ``half-boxcar'' filter and a Markovian filter with a second adjustable threshold; these filters eliminate the dominant source of error in the boxcar filter, and compare favorably to the optimal filter. For each filter, we derive analytic results for the decay in average fidelity and verify them with numerical simulations.https://quantum-journal.org/papers/q-2020-11-04-358/pdf/ |
| spellingShingle | Razieh Mohseninia Jing Yang Irfan Siddiqi Andrew N. Jordan Justin Dressel Always-On Quantum Error Tracking with Continuous Parity Measurements Quantum |
| title | Always-On Quantum Error Tracking with Continuous Parity Measurements |
| title_full | Always-On Quantum Error Tracking with Continuous Parity Measurements |
| title_fullStr | Always-On Quantum Error Tracking with Continuous Parity Measurements |
| title_full_unstemmed | Always-On Quantum Error Tracking with Continuous Parity Measurements |
| title_short | Always-On Quantum Error Tracking with Continuous Parity Measurements |
| title_sort | always on quantum error tracking with continuous parity measurements |
| url | https://quantum-journal.org/papers/q-2020-11-04-358/pdf/ |
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