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

Chinese Physics Letters

Engineering Knill–Laflamme–Milburn Entanglement via Dissipation and Coherent Population Trapping in Rydberg Atoms

Rui Li, Shuang He, Zhi-Jun Meng, Zhao Jin, Wei‐Jiang Gong

Published May 15, 2023• 4 citations
Publisher

Abstract

We present a scheme for dissipatively preparing bipartite Knill–Laflamme–Milburn (KLM) entangled state in a neutral atom system, where the spontaneous emission of excited Rydberg states, combined with the coherent population trapping, is actively exploited to engineer a steady KLM state from an arbitrary initial state. Instead of commonly used antiblockade dynamics of two Rydberg atoms, we particularly utilize the Rydberg–Rydberg interaction as the pumping source to drive the undesired states so that it is unnecessary to satisfy a certain relation with laser detuning. The numerical simulation of the master equation signifies that both the fidelity and the purity above 98% is available with the current feasible parameters, and the corresponding steady-state fidelity is robust to the variations of the dynamical parameters.

DOI
10.1088/0256-307x/40/6/060302

Related papers

Engineering steady Knill-Laflamme-Milburn state of Rydberg atoms by dissipation

Dongxiao Li, Xiao‐Qiang Shao, Jin-Hui Wu +2 more

The Knill-Laflamme-Milburn (KLM) states have been proved to be a useful resource for quantum information processing [Nature409, 46 (2001)]. For atomic KLM states, several schemes have been put forward based on the time-dependent unitary dynamics, but the dissipative generation of these states has not been reported. This work discusses the possibility for creating different forms of bipartite KLM states in neutral atom system, where the spontaneous emission of excited Rydberg states, combined with the Rydberg antiblockade mechanism, is actively exploited to engineer a steady KLM state from an arbitrary initial state. The numerical simulation of the master equation signifies that a fidelity above 99% is available with the current experimental parameters.

arXiv:1803.02158•Optics Express•Jan 23, 2018•30 citations

Fast and dephasing-tolerant preparation of steady Knill-Laflamme-Milburn states via dissipative Rydberg pumping

Ri‐Hua Zheng, Yang Xiao, Shi‐Lei Su +5 more

We propose a fast and dephasing-tolerant scheme for the preparation of steady Knill-Laflamme-Milburn (KLM) state between a pair of Rydberg atoms by dissipation. In this scheme, arbitrary initial state can be engineered to the KLM state with high fidelity (99.24%). Compared to most schemes based on Rydberg dissipation dynamics, the time to prepare steady state can be significantly reduced in our scheme $(80 \ensuremath{\mu}\mathrm{s})$ due to the use of strong resonant dipole-dipole interactions. In addition, the scheme can effectively suppress the dephasing error of the Rydberg atoms caused by interatomic distance fluctuations, which may severely disrupt the desired systematic dynamics. Thus the present scheme is of interest and deserves further experimental investigation to enrich the dissipation dynamics based on the Rydberg atoms.

Physical Review A•May 4, 2021•40 citations

Accelerated and Noise‐Resistant Protocol of Dissipation‐Based Knill–Laflamme–Milburn State Generation with Lyapunov Control

Yu Wang, Chang‐Sheng Hu, Zhi‐Cheng Shi +3 more

Abstract A protocol to generate steady Knill–Laflamme–Milburn (KLM) states of two Rydberg atoms with dissipation and Lyapunov control is proposed. Herein, combining with the quantum Zeno dynamics and the Rydberg antiblockade, a unique and steady solution of the master equation of the system is obtained, which satisfies the definition of KLM states. Furthermore, to polish the convergence rate, well‐designed additional coherent control (ACC) fields with Lyapunov control are added into the traditional dissipation process. Numerical simulation reveals that the steady target state generation is prominently accelerated and the protocol is robust against the stochastic noise errors caused by laser fields. It is hoped that the work may provide an alternative protocol to polish the generation of entanglement.

Annalen der Physik•Mar 19, 2019•22 citations

Dissipative entanglement preparation via Rydberg antiblockade and Lyapunov control

Zong-Xing Ding, Chang-Sheng Hu, Li-Tuo Shen +3 more

Abstract Preparation of entangled steady states via dissipation and pumping in Rydberg atoms has been recently found to be useful for quantum information processing. The driven-dissipative dynamics is closely related to the natural linewidth of the Rydberg states and can be usually modulated by engineering the thermal reservior. Instead of modifying the effectively radiative decay, we propose an alternatively optimized scheme, which combines the resonant Rydberg antiblockade excitation and the Lyapunov control of the ground states to speed up the prepration of the singlet state for two interacting Rydberg atoms. The acceleration process strongly depends on the initial state of the system with respect to the initial coherence between the singlet state and decoherence-sensitive bright state. We study the optimal parameter regime for fast entanglement preparation and the robustness of the fidelity against random noises. The numerical results show that a fidelity above 0.99 can be achieved around 0.4 ms with the current experimental parameters. The scheme may be generalized for preparation of more complicate multi-atom entangled states.

arXiv:1811.11126•Laser Physics Letters•Mar 22, 2019•8 citations

Cooling neutral atoms into maximal entanglement in the Rydberg blockade regime

Wei-Lin Mu, Xiaoxuan Li, Xiao‐Qiang Shao

We propose a cooling scheme to prepare stationary entanglement of neutral atoms in the Rydberg blockade regime by the combination of periodically collective laser pumping and dissipation. In each cycle, the controlled unitary dynamics process can selectively pump atoms away from the nontarget state while keeping the target state unchanged. The subsequent dissipative process redistributes the populations of ground states through the engineered spontaneous emission. After a number of cycles, the system will eventually be stabilized into the desired steady state, independent of the initial state. This protocol does not rely on coherent addressing of individual neutral atoms or fine control of Rydberg interaction intensity, which can, in principle, greatly improve the feasibility of experiments in related fields.

arXiv:2208.08013•Optics Letters•Aug 16, 2022•2 citations

Fast dissipative preparation of three-dimensional entangled states for two Rydberg atoms via Lyapunov control

Zong-Xing Ding, Chang‐Sheng Hu, Li-Tuo Shen +3 more

Abstract By using the Lyapunov control approach—an optimization algorithm, we propose a dissipative scheme for efficiently preparing the three-dimensional entangled state of two Rydberg atoms, which subject to Rydberg–Rydberg interactions at the antiblockade regime. The steady target state is the unique dark state of the two-atom system, and is achieved with high fidelity under the Rydberg pumping and the atomic spontaneous emission. The time required to settle into the high-fidelity steady state is greatly accelerated by the help of Lyapunov control, which takes effects while the system is initially prepared in the states containing coherence between the dark state and decoherence-sensitive bright states. The numerical results show that a fidelity of the steady three-dimensional entangled state above 0.99 can be achieved around 2.2 ms with the current experimental conditions. We study in detail the optimal control parameters and show the robustness of the scheme against random noises. The scheme may be generalized for preparation of more complicate multi-atom entangled states.

Laser Physics Letters•Jan 25, 2021•2 citations
We present a scheme for dissipatively preparing bipartite Knill–Laflamme–Milburn (KLM) entangled state in a neutral atom system, where the spontaneous emission of excited Rydberg states, combined with the coherent population trapping, is actively exploited to engineer a steady KLM state from an arbitrary initial state. Instead of commonly used antiblockade dynamics of two Rydberg atoms, we particularly utilize the Rydberg–Rydberg interaction as the pumping source to drive the undesired states so that it is unnecessary to satisfy a certain relation with laser detuning. The numerical simulation of the master equation signifies that both the fidelity and the purity above 98% is available with the current feasible parameters, and the corresponding steady-state fidelity is robust to the variations of the dynamical parameters.
The Knill-Laflamme-Milburn (KLM) states have been proved to be a useful resource for quantum information processing [Nature409, 46 (2001)]. For atomic KLM states, several schemes have been put forward based on the time-dependent unitary dynamics, but the dissipative generation of these states has not been reported. This work discusses the possibility for creating different forms of bipartite KLM states in neutral atom system, where the spontaneous emission of excited Rydberg states, combined with the Rydberg antiblockade mechanism, is actively exploited to engineer a steady KLM state from an arbitrary initial state. The numerical simulation of the master equation signifies that a fidelity above 99% is available with the current experimental parameters.
We propose a fast and dephasing-tolerant scheme for the preparation of steady Knill-Laflamme-Milburn (KLM) state between a pair of Rydberg atoms by dissipation. In this scheme, arbitrary initial state can be engineered to the KLM state with high fidelity (99.24%). Compared to most schemes based on Rydberg dissipation dynamics, the time to prepare steady state can be significantly reduced in our scheme $(80 \ensuremath{\mu}\mathrm{s})$ due to the use of strong resonant dipole-dipole interactions. In addition, the scheme can effectively suppress the dephasing error of the Rydberg atoms caused by interatomic distance fluctuations, which may severely disrupt the desired systematic dynamics. Thus the present scheme is of interest and deserves further experimental investigation to enrich the dissipation dynamics based on the Rydberg atoms.
Abstract A protocol to generate steady Knill–Laflamme–Milburn (KLM) states of two Rydberg atoms with dissipation and Lyapunov control is proposed. Herein, combining with the quantum Zeno dynamics and the Rydberg antiblockade, a unique and steady solution of the master equation of the system is obtained, which satisfies the definition of KLM states. Furthermore, to polish the convergence rate, well‐designed additional coherent control (ACC) fields with Lyapunov control are added into the traditional dissipation process. Numerical simulation reveals that the steady target state generation is prominently accelerated and the protocol is robust against the stochastic noise errors caused by laser fields. It is hoped that the work may provide an alternative protocol to polish the generation of entanglement.
Abstract Preparation of entangled steady states via dissipation and pumping in Rydberg atoms has been recently found to be useful for quantum information processing. The driven-dissipative dynamics is closely related to the natural linewidth of the Rydberg states and can be usually modulated by engineering the thermal reservior. Instead of modifying the effectively radiative decay, we propose an alternatively optimized scheme, which combines the resonant Rydberg antiblockade excitation and the Lyapunov control of the ground states to speed up the prepration of the singlet state for two interacting Rydberg atoms. The acceleration process strongly depends on the initial state of the system with respect to the initial coherence between the singlet state and decoherence-sensitive bright state. We study the optimal parameter regime for fast entanglement preparation and the robustness of the fidelity against random noises. The numerical results show that a fidelity above 0.99 can be achieved around 0.4 ms with the current experimental parameters. The scheme may be generalized for preparation of more complicate multi-atom entangled states.
We propose a cooling scheme to prepare stationary entanglement of neutral atoms in the Rydberg blockade regime by the combination of periodically collective laser pumping and dissipation. In each cycle, the controlled unitary dynamics process can selectively pump atoms away from the nontarget state while keeping the target state unchanged. The subsequent dissipative process redistributes the populations of ground states through the engineered spontaneous emission. After a number of cycles, the system will eventually be stabilized into the desired steady state, independent of the initial state. This protocol does not rely on coherent addressing of individual neutral atoms or fine control of Rydberg interaction intensity, which can, in principle, greatly improve the feasibility of experiments in related fields.
Abstract By using the Lyapunov control approach—an optimization algorithm, we propose a dissipative scheme for efficiently preparing the three-dimensional entangled state of two Rydberg atoms, which subject to Rydberg–Rydberg interactions at the antiblockade regime. The steady target state is the unique dark state of the two-atom system, and is achieved with high fidelity under the Rydberg pumping and the atomic spontaneous emission. The time required to settle into the high-fidelity steady state is greatly accelerated by the help of Lyapunov control, which takes effects while the system is initially prepared in the states containing coherence between the dark state and decoherence-sensitive bright states. The numerical results show that a fidelity of the steady three-dimensional entangled state above 0.99 can be achieved around 2.2 ms with the current experimental conditions. We study in detail the optimal control parameters and show the robustness of the scheme against random noises. The scheme may be generalized for preparation of more complicate multi-atom entangled states.