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:2103.07907 · Physical Review A

Geometric manipulation of a decoherence-free subspace in atomic ensembles

Dongni Shao Chen, Si Luo, Ying-Dan Wang, Stefano Chesi, Mahn‐Soo Choi

Published Feb 28, 2022• 3 citations
arXivHTMLPDF

Abstract

We consider an ensemble of atoms with $\mathrm{\ensuremath{\Lambda}}$-type level structure trapped in a single-mode cavity, and propose a geometric scheme of coherent manipulation of quantum states on the subspace of zero-energy states within the quantum Zeno subspace of the system. We find that the particular subspace inherits the decoherence-free nature of the quantum Zeno subspace and features a symmetry-protected degeneracy, fulfilling all the conditions for a universal scheme of arbitrary unitary operations on it.

DOI
10.1103/physreva.105.022627

Related papers

Geometric manipulation of ensembles of atoms on an atom chip for quantum computation

Yi-Cong Zheng, Todd A. Brun

We propose a feasible scheme to achieve quantum computation based on geometric manipulation of ensembles of atoms and analyze it for neutral rubidium atoms magnetically trapped in planoconcave microcavities on an atom chip. The geometric operations are accomplished by optical excitation of a single atom into a Rydberg state in a constant electric field. Strong dipole-dipole interactions and incident lasers drive the dark state of the atom ensembles to undergo cyclic evolutions that realize a universal set of quantum gates. Such geometric manipulation turns out naturally to protect the qubits from the errors induced by nonuniform laser illumination as well as cavity loss. The gate performance and decoherence processes are assessed by numerical simulation.

arXiv:1109.5009•Physical Review A•Sep 18, 2012•13 citations

Realization of universal nonadiabatic geometric control on decoherence-free qubits in the XY model

Vahid Azimi Mousolou

A fundamental requirement of quantum information processing is the protection from the adverse effects of decoherence and noise. Decoherence-free subspaces and geometric processing are important steps of quantum information protection. Here, we provide a new experimentally feasible scheme to combine decoherence-free subspaces with nonadiabatic geometric manipulations to attain a universal quantum computation. The proposed scheme is different from previous proposals and is based on the typical XY interaction coupling, which can be set up in various nano-engineered systems and therefore open up for realization of nonadiabatic holonomic quantum computation in decoherence-free subspaces.

arXiv:1710.02281•Europhysics Letters (EPL)•Jan 1, 2018•15 citations

Engineering tunable decoherence-free subspaces with collective atom-cavity interactions

Lyryl H. C. Vaecairn, J. Reilly, John Drew Wilson +2 more

We propose schemes to design and control a time-dependent decoherence-free subspace (DFS) in a dissipative atom-cavity system. These schemes use atoms with three internal energy levels, which allows for the DFS to be multidimensional---a condition important for quantum sensing, simulation, and computation. We consider the use of tunable external driving lasers to transfer the system from a coherent spin state to a highly degenerate DFS. We find that the typical state in the DFS is highly entangled. Throughout evolution the state is kept in an instantaneous DFS, thereby allowing for pure states to be prepared. We develop adiabatic shortcuts to carry out this evolution with higher purity and fidelity than standard adiabatic and dissipative methods.

arXiv:2412.02921•Physical Review A•Mar 31, 2025•4 citations

Universal quantum computation in a neutral-atom decoherence-free subspace

E. Brion, Line Hjortshøj Pedersen, Klaus Mølmer +2 more

In this paper, we propose a way to achieve protected universal computation in a neutral-atom quantum computer subject to collective dephasing. Our proposal relies on the existence of a decoherence-free subspace (DFS), resulting from symmetry properties of the errors. After briefly describing the physical system and the error model considered, we show how to encode information into the DFS and build a complete set of safe universal gates. Finally, we provide numerical simulations for the fidelity of the different gates in the presence of time-dependent phase errors and discuss their performance and practical feasibility.

arXiv:quant-ph/0611246•Physical Review A•Mar 21, 2007•29 citations

Universal Nonadiabatic Geometric Gates in Two-Qubit Decoherence-Free Subspaces

Guofu Xu, Guilu Long

Geometric quantum computation in decoherence-free subspaces is of great practical importance because it can protect quantum information from both control errors and collective dephasing. However, previous proposed schemes have either states leakage or four-body interactions problems. Here, we propose a feasible scheme without these two problems. Our scheme is realized in two-qubit decoherence-free subspaces. Since the Hamiltonian we use is generic, our scheme looks promising to be demonstrated experimentally in different systems, including superconducting charge qubits.

Scientific Reports•Oct 29, 2014•74 citations

Generation of SU(2) Coherent States for a Cavity Mode and a Collective Atomic Mode

Zheng Shi-Biao

We propose a scheme for generation of SU(2) coherent states for an atomic ensemble and a cavity mode. In the scheme a collection of two-level atoms resonantly interact with a single-mode quantized field. Under certain conditions, the system can evolve from a Fock state to a highly entangled SU(2) coherent state. The operation speed increases as the number of atoms increases, which is important in view of decoherence.

Communications in Theoretical Physics•May 1, 2009•0 citations
We consider an ensemble of atoms with \ensuremathΛ\mathrm{\ensuremath{\Lambda}}\ensuremathΛ-type level structure trapped in a single-mode cavity, and propose a geometric scheme of coherent manipulation of quantum states on the subspace of zero-energy states within the quantum Zeno subspace of the system. We find that the particular subspace inherits the decoherence-free nature of the quantum Zeno subspace and features a symmetry-protected degeneracy, fulfilling all the conditions for a universal scheme of arbitrary unitary operations on it.
We propose a feasible scheme to achieve quantum computation based on geometric manipulation of ensembles of atoms and analyze it for neutral rubidium atoms magnetically trapped in planoconcave microcavities on an atom chip. The geometric operations are accomplished by optical excitation of a single atom into a Rydberg state in a constant electric field. Strong dipole-dipole interactions and incident lasers drive the dark state of the atom ensembles to undergo cyclic evolutions that realize a universal set of quantum gates. Such geometric manipulation turns out naturally to protect the qubits from the errors induced by nonuniform laser illumination as well as cavity loss. The gate performance and decoherence processes are assessed by numerical simulation.
A fundamental requirement of quantum information processing is the protection from the adverse effects of decoherence and noise. Decoherence-free subspaces and geometric processing are important steps of quantum information protection. Here, we provide a new experimentally feasible scheme to combine decoherence-free subspaces with nonadiabatic geometric manipulations to attain a universal quantum computation. The proposed scheme is different from previous proposals and is based on the typical XY interaction coupling, which can be set up in various nano-engineered systems and therefore open up for realization of nonadiabatic holonomic quantum computation in decoherence-free subspaces.
We propose schemes to design and control a time-dependent decoherence-free subspace (DFS) in a dissipative atom-cavity system. These schemes use atoms with three internal energy levels, which allows for the DFS to be multidimensional---a condition important for quantum sensing, simulation, and computation. We consider the use of tunable external driving lasers to transfer the system from a coherent spin state to a highly degenerate DFS. We find that the typical state in the DFS is highly entangled. Throughout evolution the state is kept in an instantaneous DFS, thereby allowing for pure states to be prepared. We develop adiabatic shortcuts to carry out this evolution with higher purity and fidelity than standard adiabatic and dissipative methods.
In this paper, we propose a way to achieve protected universal computation in a neutral-atom quantum computer subject to collective dephasing. Our proposal relies on the existence of a decoherence-free subspace (DFS), resulting from symmetry properties of the errors. After briefly describing the physical system and the error model considered, we show how to encode information into the DFS and build a complete set of safe universal gates. Finally, we provide numerical simulations for the fidelity of the different gates in the presence of time-dependent phase errors and discuss their performance and practical feasibility.
Geometric quantum computation in decoherence-free subspaces is of great practical importance because it can protect quantum information from both control errors and collective dephasing. However, previous proposed schemes have either states leakage or four-body interactions problems. Here, we propose a feasible scheme without these two problems. Our scheme is realized in two-qubit decoherence-free subspaces. Since the Hamiltonian we use is generic, our scheme looks promising to be demonstrated experimentally in different systems, including superconducting charge qubits.