Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Condition for fault-tolerant quantum computation with a cavity-QED scheme

Hayato Goto, Kouichi Ichimura

Published Sep 10, 2010• 17 citations
Publisher

Abstract

A condition for fault-tolerant quantum computation (FTQC) with cavity schemes is discussed. It is shown that the condition is very hard if the standard error threshold of FTQC is simply applied. To relax the condition, we propose to combine the cavity-quantum-electrodynamics (QED) scheme proposed by Duan et al. [Phys. Rev. A 72, 032333 (2005)] and Xiao et al. [Phys. Rev. A 70, 042314 (2004)] with the recently proposed FTQC scheme with probabilistic two-qubit gates [Goto and Ichimura, Phys. Rev. A 80, 040303(R) (2009)]. It is shown that the condition for FTQC is dramatically relaxed compared to the case of the standard threshold. The optimization of the cavity-QED scheme is also discussed.

DOI
10.1103/physreva.82.032311

Related papers

Fault-tolerant quantum computation with probabilistic two-qubit gates

Hayato Goto, Kouichi Ichimura

A scheme for fault-tolerant quantum computation (FTQC) with probabilistic two-qubit gates is proposed. The error thresholds for FTQC are estimated by numerical simulations, where the conditional error probability (the error probability under the condition of ``success'') is taken into account in addition to the failure probability. As a result, it turns out that FTQC is possible even if the failure probability is as high as 10% (5%) under the condition that the conditional error probability is lower than about 0.03% (0.3%). These results mean that the present scheme has a great advantage in using probabilistic two-qubit gates.

Physical Review A•Oct 20, 2009•11 citations

Suitable fault-tolerant schemes for cavity-QED-based quantum computation

Rui Asaoka, Yuuki Tokunaga, Rina Kanamoto +3 more

We show that the requirement for fault-tolerant quantum computation based on cavity-QED is dramatically relaxed by applying the suitable fault-tolerant schemes and gate error optimization for chosen two-qubit gate method.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 1, 2020•1 citation

Fault-tolerant logical state construction based on cavity-QED network

Rui Asaoka, Yasunari Suzuki, Yuuki Tokunaga

Exploring an efficient and scalable architecture of fault-tolerant quantum computing (FTQC) is vital for demonstrating useful quantum computing. Here, we propose and evaluate a scalable and practical architecture with a cavity-quantum-electrodynamics (CQED) network. Our architecture takes advantage of the stability of neutral atoms and the flexibility of a CQED network. We show a concrete framework for implementing surface codes and numerically analyze the logical error rate and threshold values beyond the simplified circuit-level noise model on several network structures. Although the requirement of CQED parameters is demanding given the current performance of experimental systems, we show that an error-decoding algorithm tailored to our proposed architecture, where the loss information of ancillary photons is utilized, greatly improves the error threshold. For example, the internal cooperativity, a good figure of merit of the cavity performance for quantum computing, required for FTQC is relaxed to 1/5 compared to the normal error-decoding for the surface code. Since our proposal and results can be extended to other LDPC codes straightforwardly, our approach will lead to achieve more reliable FTQC using CQED.

arXiv:2503.11500•Mar 14, 2025•0 citations

Requirements for fault-tolerant quantum computation with cavity-QED-based atom-atom gates mediated by a photon with a finite pulse length

Rui Asaoka, Yuuki Tokunaga, Rina Kanamoto +2 more

We analyze the requirements for fault-tolerant quantum computation with atom-atom gates based on cavity quantum electrodynamics (cQED) mediated by a photon with a finite pulse length. For short photon pulses, the distorted shape of the reflected pulses from the cQED system is a serious error source. In the previous study by Goto and Ichimura [Phys. Rev. A 82, 032311 (2010)], only the photon loss is minimized without considering the shape distortion to optimize the system parameters. Here we show an improved optimization method to minimize the infidelity due to the shape distortion and the photon losses in a well-balanced manner for the fault-tolerant scheme using probabilistic gates [Phys. Rev. A 80, 040303(R) (2009)]. Under this optimization, we discuss the fault-tolerant quantum computing requirement for short pulses. Finally, we show that reducing the cavity length is an effective way to reduce the errors of this type of gate in the case of short photon pulses.

arXiv:2104.00945•Physical Review A•Oct 7, 2021•8 citations

Quantum error mitigation for fault-tolerant quantum computing

Yasunari Suzuki, Suguru Endo, Keisuke Fujii +1 more

Fault-tolerant quantum computing (FTQC) is a form of universal quantum computing that suppresses physical errors via quantum error correction (QEC). On the other hand, it is expected that the available code distance and the $T$-gate count will be restricted in the early years of FTQC. Meanwhile, quantum error mitigation (QEM) was recently introduced for suppressing errors in noisy intermediate-scale quantum (NISQ) devices; it improves the computation accuracy of near-term quantum algorithms with its overhead being a greater number of samples. In this work, we integrate QEC and QEM into an efficient FTQC architecture that effectively increases the code distance and $T$-gate count. Our scheme will dramatically alleviate the required qubit count by tens of percent at the cost of a constant multiplicative sampling overhead within $10^2$ in a wide range of regimes from the post-NISQ era to early FTQC regime, which necessitates the order of from $10^4$ to $10^{10}$ logical operations. While it has been widely believed that there do not exist useful applications in post-NISQ regimes due to a chasm between the NISQ and FTQC regimes such as overheads for encoding and $T$-gate distillations, our scheme can continuously bridge the two distinct regimes.

arXiv:2010.03887•Bulletin of the American Physical Society•Oct 8, 2020•11 citations

An Introduction to Fault-Tolerant Quantum Computation and its Overhead Reduction Schemes

IlKwon Sohn, Jun Heo

A quantum computer is a powerful machine that provides a new approach to information processing based on quantum mechanics. However, basically, qubits are very vulnerable to errors, thus a quantum error correction code (QECC) is needed to build a reliable quantum computer. Moreover, simply using QECCs is not sufficient in order that a quantum computer can tolerate errors. In quantum computation, each operation must be performed on the encoded states. Even when the gates used to perform these operations are noisy, the quantum computation must be tolerable to the errors. This is called fault-tolerant quantum computation and it is an essential condition for implementing a quantum computer. However, considering the fault tolerance, the overhead of the quantum computer increases exponentially. In this paper, we introduce fault-tolerant quantum computation and schemes to reduce the its overhead.

International Conference on Ubiquitous and Future Networks•Jul 1, 2018•7 citations
A condition for fault-tolerant quantum computation (FTQC) with cavity schemes is discussed. It is shown that the condition is very hard if the standard error threshold of FTQC is simply applied. To relax the condition, we propose to combine the cavity-quantum-electrodynamics (QED) scheme proposed by Duan et al. [Phys. Rev. A 72, 032333 (2005)] and Xiao et al. [Phys. Rev. A 70, 042314 (2004)] with the recently proposed FTQC scheme with probabilistic two-qubit gates [Goto and Ichimura, Phys. Rev. A 80, 040303(R) (2009)]. It is shown that the condition for FTQC is dramatically relaxed compared to the case of the standard threshold. The optimization of the cavity-QED scheme is also discussed.
A scheme for fault-tolerant quantum computation (FTQC) with probabilistic two-qubit gates is proposed. The error thresholds for FTQC are estimated by numerical simulations, where the conditional error probability (the error probability under the condition of ``success'') is taken into account in addition to the failure probability. As a result, it turns out that FTQC is possible even if the failure probability is as high as 10% (5%) under the condition that the conditional error probability is lower than about 0.03% (0.3%). These results mean that the present scheme has a great advantage in using probabilistic two-qubit gates.
Exploring an efficient and scalable architecture of fault-tolerant quantum computing (FTQC) is vital for demonstrating useful quantum computing. Here, we propose and evaluate a scalable and practical architecture with a cavity-quantum-electrodynamics (CQED) network. Our architecture takes advantage of the stability of neutral atoms and the flexibility of a CQED network. We show a concrete framework for implementing surface codes and numerically analyze the logical error rate and threshold values beyond the simplified circuit-level noise model on several network structures. Although the requirement of CQED parameters is demanding given the current performance of experimental systems, we show that an error-decoding algorithm tailored to our proposed architecture, where the loss information of ancillary photons is utilized, greatly improves the error threshold. For example, the internal cooperativity, a good figure of merit of the cavity performance for quantum computing, required for FTQC is relaxed to 1/5 compared to the normal error-decoding for the surface code. Since our proposal and results can be extended to other LDPC codes straightforwardly, our approach will lead to achieve more reliable FTQC using CQED.
We analyze the requirements for fault-tolerant quantum computation with atom-atom gates based on cavity quantum electrodynamics (cQED) mediated by a photon with a finite pulse length. For short photon pulses, the distorted shape of the reflected pulses from the cQED system is a serious error source. In the previous study by Goto and Ichimura [Phys. Rev. A 82, 032311 (2010)], only the photon loss is minimized without considering the shape distortion to optimize the system parameters. Here we show an improved optimization method to minimize the infidelity due to the shape distortion and the photon losses in a well-balanced manner for the fault-tolerant scheme using probabilistic gates [Phys. Rev. A 80, 040303(R) (2009)]. Under this optimization, we discuss the fault-tolerant quantum computing requirement for short pulses. Finally, we show that reducing the cavity length is an effective way to reduce the errors of this type of gate in the case of short photon pulses.
Fault-tolerant quantum computing (FTQC) is a form of universal quantum computing that suppresses physical errors via quantum error correction (QEC). On the other hand, it is expected that the available code distance and the TTT-gate count will be restricted in the early years of FTQC. Meanwhile, quantum error mitigation (QEM) was recently introduced for suppressing errors in noisy intermediate-scale quantum (NISQ) devices; it improves the computation accuracy of near-term quantum algorithms with its overhead being a greater number of samples. In this work, we integrate QEC and QEM into an efficient FTQC architecture that effectively increases the code distance and TTT-gate count. Our scheme will dramatically alleviate the required qubit count by tens of percent at the cost of a constant multiplicative sampling overhead within 10210^2102 in a wide range of regimes from the post-NISQ era to early FTQC regime, which necessitates the order of from 10410^4104 to 101010^{10}1010 logical operations. While it has been widely believed that there do not exist useful applications in post-NISQ regimes due to a chasm between the NISQ and FTQC regimes such as overheads for encoding and TTT-gate distillations, our scheme can continuously bridge the two distinct regimes.
A quantum computer is a powerful machine that provides a new approach to information processing based on quantum mechanics. However, basically, qubits are very vulnerable to errors, thus a quantum error correction code (QECC) is needed to build a reliable quantum computer. Moreover, simply using QECCs is not sufficient in order that a quantum computer can tolerate errors. In quantum computation, each operation must be performed on the encoded states. Even when the gates used to perform these operations are noisy, the quantum computation must be tolerable to the errors. This is called fault-tolerant quantum computation and it is an essential condition for implementing a quantum computer. However, considering the fault tolerance, the overhead of the quantum computer increases exponentially. In this paper, we introduce fault-tolerant quantum computation and schemes to reduce the its overhead.