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

arXiv:2105.04914 · Physical Review Applied

Implementation of Hybridly Protected Quantum Gates

Chunfeng Wu, Chunfang Sun, Gangcheng Wang, Xun‐Li Feng, X. X. Yi

Published Mar 1, 2022• 2 citations
arXivHTMLPDF

Abstract

We explore the implementation of hybridly protected quantum operations combining the merits of geometry and holonomy, dynamical decoupling approach, and dephasing-free feature based on a simple and experimentally achievable spin model. The implementation of the quantum operations can be achieved in different physical systems with controllable parameters. The protected quantum operations are hence controllable and well suited for resolving various quantum-computation tasks, such as executing quantum error-correction codes or quantum error mitigation. Our scheme is based on an experimentally achievable Hamiltonian with reduced requirement of computational resources and thus, it brings us closer towards realizing protected quantum operations for resolving quantum-computation tasks in near-term quantum devices.

DOI
10.1103/physrevapplied.17.034003

Related papers

Hybrid noise protection of logical qubits for universal quantum computation

Zhao-Ming Wang, Feng-Hua Ren, Mark Byrd +1 more

Quantum computers now show the promise of surpassing any possible classical machine. However, errors limit this ability and current machines do not have the ability to implement error correcting codes due to the limited number of qubits and limited control. Therefore, dynamical decoupling (DD) and encodings that limit noise with fewer qubits are more promising. For these reasons, we put forth a model of universal quantum computation that has many advantages over strategies that require a large overhead such as the standard quantum-error correcting codes. First, we separate collective noise from individual noises on physical qubits and use a decoherence-free subspace that uses just two qubits for its encoding to eliminate collective noise. Second, our bath model is very general as it uses a spin-boson-type bath but without any Markovian assumption. Third, we are able to either use a steady global magnetic field or to devise a set of DD pulses that remove much of the remaining noise and commute with the logical operations on the encoded qubit. This allows removal of noise while implementing gate operations. Numerical support is given for this hybrid protection strategy which provides an efficient approach to deal with the decoherence problems in quantum computation and is experimentally viable for several current quantum computing systems. This is emphasized by a recent experiment on superconducting qubits which shows promise for increasing the number of gates that can be implemented reliably with some realistic parameter assumptions.

arXiv:2306.15144•Physical Review A•Aug 10, 2023•6 citations

Decoherence-protected holonomic gates with reduced requirements for physical resources

Chunfeng Wu, Chunfang Sun, Jiangang Ma +3 more

We study the implementation of holonomic quantum gates preserved from arbitrary single-qubit and two-qubit decoherence or errors using a dynamical decoupling approach. To integrate the holonomic feature with the dynamical decoupling technique, we require only one auxiliary qubit for single-qubit gates and no auxiliary qubit for two-qubit gates. Our scheme uses far fewer physical qubits to achieve this integration compared to existing proposals in the literature. Moreover, the scheme is based on system interactions that can be experimentally realized with superconducting qubits. These advantages suggest that our scheme is a promising step toward developing noise-resistant quantum devices.

Physical Review Applied•Apr 7, 2025•0 citations

Holonomic Quantum Computation in Surface Codes

Chunfeng Wu, Yimin Wang, Xun‐Li Feng +1 more

It is well known that surface codes are favorable candidates toward realizing large-scale fault-tolerant quantum computation. While methods to reduce errors by surface codes have been well explored, it is still challenging to achieve small-enough errors as stated by the threshold theorem in practical experimental settings. This prompts the integration of surface codes and protected quantum operations to further mitigate the negative effect of errors, creating the challenge of executing protected surface codes. In this work, we propose one scheme to perform holonomic quantum operations in a physical system by use of auxiliary qubits. The system Hamiltonian describes a quantum spin model with adjustable coupling strength. Various noncommutable single-qubit and nontrivial two-qubit holonomic gates are applicable on the basis of the interaction between the auxiliary qubits and physical qubits. By considering a two-dimensional lattice of qubits, we explore the execution of surface codes. The utilization rate of physical qubits as data qubits is about $24.7\mathrm{%}$ in executing the protected surface codes. Our scheme is based on an experimentally achievable Hamiltonian and thus it brings us closer to realizing protected quantum operations on quantum-error-correction codes with a modest resource.

Physical Review Applied•Jan 28, 2020•23 citations

Protected Quantum Computing: Interleaving Gate Operations with Dynamical Decoupling Sequences

Jingfu Zhang, Alexandre M. Souza, Frederico Dias Brandao +1 more

Implementing precise operations on quantum systems is one of the biggest challenges for building quantum devices in a noisy environment. Dynamical decoupling attenuates the destructive effect of the environmental noise, but so far, it has been used primarily in the context of quantum memories. Here, we experimentally demonstrate a general scheme for combining dynamical decoupling with quantum logical gate operations using the example of an electron-spin qubit of a single nitrogen-vacancy center in diamond. We achieve process fidelities >98% for gate times that are 2 orders of magnitude longer than the unprotected dephasing time T2.

arXiv:1307.5162•Physical Review Letters•Feb 6, 2014•109 citations

Experimental protection of quantum gates against decoherence and control errors

Alexandre M. Souza, Gonzalo A. Álvarez, Dieter Suter

One of the biggest challenges for implementing quantum devices is the requirement to perform accurate quantum gates. The destructive effects of interactions with the environment present some of the most difficult obstacles that must be overcome for precise quantum control. In this work we implement a proof of principle experiment of quantum gates protected against a fluctuating environment and control pulse errors using dynamical decoupling techniques. We show that decoherence can be reduced during the application of quantum gates. High-fidelity quantum gates can be achieved even if the gate time exceeds the free evolution decoherence time by one order of magnitude and for protected operations consisting of up to 330 individual control pulses.

arXiv:1206.2933•Physical Review A•Nov 5, 2012•36 citations

Decoherence mitigation for geometric quantum computation

Xiangyu Sun, P. Z. Zhao

Geometric phases depend only on the evolution path determined by the closed circuit in the projective Hilbert space but not on evolution details of the quantum system, leading to geometric quantum computation possessing some intrinsic robustness against control errors. Coordinated with dynamical decoupling, geometric quantum computation admits additional resilience to the environment-induced decoherence. However, the previous schemes of geometric quantum computation protected by dynamical decoupling require multiple physical qubits to encode a logical qubit, which undoubtedly increases the consumption of physical-qubit resources and the difficulty in the implementation of the logical-qubit manipulation based on physical-qubit driving. In this work, we put forward a scheme of decoherence-mitigated geometric quantum computation based only on physical qubits rather than logical qubits, hence avoiding the additional overhead of physical-qubit resources for logical-qubit encoding as well as the difficulty in the manipulation of logical qubits. Moreover, our scheme focuses on the most general interaction between an individual qubit and its environment so that it mitigates not just dephasing noise but rather regular decoherence. Our proposal thus represents a more realistic and effective approach towards the realization of geometric control with decoherence mitigation.

arXiv:2509.03856•Physical Review A•Aug 13, 2025•2 citations
We explore the implementation of hybridly protected quantum operations combining the merits of geometry and holonomy, dynamical decoupling approach, and dephasing-free feature based on a simple and experimentally achievable spin model. The implementation of the quantum operations can be achieved in different physical systems with controllable parameters. The protected quantum operations are hence controllable and well suited for resolving various quantum-computation tasks, such as executing quantum error-correction codes or quantum error mitigation. Our scheme is based on an experimentally achievable Hamiltonian with reduced requirement of computational resources and thus, it brings us closer towards realizing protected quantum operations for resolving quantum-computation tasks in near-term quantum devices.
Quantum computers now show the promise of surpassing any possible classical machine. However, errors limit this ability and current machines do not have the ability to implement error correcting codes due to the limited number of qubits and limited control. Therefore, dynamical decoupling (DD) and encodings that limit noise with fewer qubits are more promising. For these reasons, we put forth a model of universal quantum computation that has many advantages over strategies that require a large overhead such as the standard quantum-error correcting codes. First, we separate collective noise from individual noises on physical qubits and use a decoherence-free subspace that uses just two qubits for its encoding to eliminate collective noise. Second, our bath model is very general as it uses a spin-boson-type bath but without any Markovian assumption. Third, we are able to either use a steady global magnetic field or to devise a set of DD pulses that remove much of the remaining noise and commute with the logical operations on the encoded qubit. This allows removal of noise while implementing gate operations. Numerical support is given for this hybrid protection strategy which provides an efficient approach to deal with the decoherence problems in quantum computation and is experimentally viable for several current quantum computing systems. This is emphasized by a recent experiment on superconducting qubits which shows promise for increasing the number of gates that can be implemented reliably with some realistic parameter assumptions.
We study the implementation of holonomic quantum gates preserved from arbitrary single-qubit and two-qubit decoherence or errors using a dynamical decoupling approach. To integrate the holonomic feature with the dynamical decoupling technique, we require only one auxiliary qubit for single-qubit gates and no auxiliary qubit for two-qubit gates. Our scheme uses far fewer physical qubits to achieve this integration compared to existing proposals in the literature. Moreover, the scheme is based on system interactions that can be experimentally realized with superconducting qubits. These advantages suggest that our scheme is a promising step toward developing noise-resistant quantum devices.
It is well known that surface codes are favorable candidates toward realizing large-scale fault-tolerant quantum computation. While methods to reduce errors by surface codes have been well explored, it is still challenging to achieve small-enough errors as stated by the threshold theorem in practical experimental settings. This prompts the integration of surface codes and protected quantum operations to further mitigate the negative effect of errors, creating the challenge of executing protected surface codes. In this work, we propose one scheme to perform holonomic quantum operations in a physical system by use of auxiliary qubits. The system Hamiltonian describes a quantum spin model with adjustable coupling strength. Various noncommutable single-qubit and nontrivial two-qubit holonomic gates are applicable on the basis of the interaction between the auxiliary qubits and physical qubits. By considering a two-dimensional lattice of qubits, we explore the execution of surface codes. The utilization rate of physical qubits as data qubits is about $24.7\mathrm{%}$ in executing the protected surface codes. Our scheme is based on an experimentally achievable Hamiltonian and thus it brings us closer to realizing protected quantum operations on quantum-error-correction codes with a modest resource.
Implementing precise operations on quantum systems is one of the biggest challenges for building quantum devices in a noisy environment. Dynamical decoupling attenuates the destructive effect of the environmental noise, but so far, it has been used primarily in the context of quantum memories. Here, we experimentally demonstrate a general scheme for combining dynamical decoupling with quantum logical gate operations using the example of an electron-spin qubit of a single nitrogen-vacancy center in diamond. We achieve process fidelities >98% for gate times that are 2 orders of magnitude longer than the unprotected dephasing time T2.
One of the biggest challenges for implementing quantum devices is the requirement to perform accurate quantum gates. The destructive effects of interactions with the environment present some of the most difficult obstacles that must be overcome for precise quantum control. In this work we implement a proof of principle experiment of quantum gates protected against a fluctuating environment and control pulse errors using dynamical decoupling techniques. We show that decoherence can be reduced during the application of quantum gates. High-fidelity quantum gates can be achieved even if the gate time exceeds the free evolution decoherence time by one order of magnitude and for protected operations consisting of up to 330 individual control pulses.
Geometric phases depend only on the evolution path determined by the closed circuit in the projective Hilbert space but not on evolution details of the quantum system, leading to geometric quantum computation possessing some intrinsic robustness against control errors. Coordinated with dynamical decoupling, geometric quantum computation admits additional resilience to the environment-induced decoherence. However, the previous schemes of geometric quantum computation protected by dynamical decoupling require multiple physical qubits to encode a logical qubit, which undoubtedly increases the consumption of physical-qubit resources and the difficulty in the implementation of the logical-qubit manipulation based on physical-qubit driving. In this work, we put forward a scheme of decoherence-mitigated geometric quantum computation based only on physical qubits rather than logical qubits, hence avoiding the additional overhead of physical-qubit resources for logical-qubit encoding as well as the difficulty in the manipulation of logical qubits. Moreover, our scheme focuses on the most general interaction between an individual qubit and its environment so that it mitigates not just dephasing noise but rather regular decoherence. Our proposal thus represents a more realistic and effective approach towards the realization of geometric control with decoherence mitigation.