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

Photonics

Protecting the Quantum Coherence of Two Atoms Inside an Optical Cavity by Quantum Feedback Control Combined with Noise-Assisted Preparation

Changxiao Li

Published Apr 25, 2024• 5 citations
Publisher

Abstract

We propose a theoretical scheme to enhance quantum coherence and obtain steady-state coherence by combining quantum feedback control and noise-assisted preparation. We investigate the effects of quantum-jump-based feedback control and noise field on the quantum coherence and excited-state population between two atoms inside an optical cavity where a noise field drives one, and the other is under quantum feedback control. It is found that steady quantum coherence can be achieved by adding an external noise field, and the quantum feedback can prolong the coherence time with partial suppression of the spontaneous emission of atoms. In addition, we study the influence of the joint action of quantum feedback and noise-assisted preparation on quantum coherence and show that the combined action of feedback control and noise-assisted preparation is more effective in enhancing steady coherence. The findings of our research offer some general guidelines for improving the steady-state coherence of coupled qubit systems and have the potential to be applied in the realm of quantum information technology.

DOI
10.3390/photonics11050400

Related papers

Controlling Entanglement by Quantum-Jump-Based Feedback

Andre R. R. Carvalho, J. J. Hope

We describe how feedback methods can be implemented to produce and stabilize entangled states of two atoms inside a cavity. Feedback control is used to engineer an effective environment dynamics, such that the entangled state to be protected is a steady state of the system. The control strategy is therefore robust with respect to external noises and fundamental decoherence sources, as spontaneous emission, for example. We also show that the scheme is mostly insensitive to practical imperfections, as detection inefficiencies and laser fluctuations.

Quantum-Atom Optics Downunder (QAO)•Jan 1, 2007•0 citations

Enhancement of coherent dipole coupling between two atoms via squeezing a cavity mode

Yan Wang, Chuang Li, Elijah M. Sampuli +3 more

We propose a theoretical method to enhance the coherent dipole coupling between two atoms in an optical cavity via parametrically squeezing the cavity mode. In the present scheme, conditions for coherent coupling are derived in detail and diverse dynamics of the system can be obtained by regulating system parameters. In the presence of environmental noise, an auxiliary squeezed field is employed to suppress and even completely eliminate the additional noise induced by squeezing. In addition, we demonstrate that our scheme enables the effective suppression of atomic spontaneous emission. The results in our investigation could be used for diverse applications in quantum technologies.

arXiv:1902.05751•Physical Review A•Feb 19, 2019•41 citations

Noise-induced quantum correlations via quantum feedback control

Jie Song, Yan Xia, Xiudong Sun

We study a physical system for creation of quantum correlations by quantum feedback control. The system is composed of two three-level atoms, each of which interacts with one of two coupled cavities. By appropriately choosing the feedback strength, we show that an arbitrary initial state can be deterministically driven to a steady-state that has a nonzero quantum discord or entanglement. It is also found that the effect of atomic spontaneous emission on quantum correlations is suppressed efficiently by increasing the frequency detuning.

Journal of the Optical Society of America B•Feb 8, 2012•10 citations

Dissipative preparation of a tripartite singlet state in coupled arrays of cavities via quantum feedback control

Xiao‐Qiang Shao, Zhihai Wang, H. D. Liu +1 more

We propose an experimentally feasible scheme for dissipative preparation of a tripartite entangled state with atoms separately trapped in an array of three coupled cavities. The combination of coherent driving fields and quantum-jump-based feedback control will drive the system into a nonequilibrium steady state, which has a nearly perfect overlap with the genuine three-atom singlet state. Different control strategies are investigated and the corresponding optimal parameters are confirmed. Moreover, the fidelity of the target state is insensitive to detection inefficiencies, and it exceeds 90% for a wide range of decoherence parameters as long as the single-atom cooperativity parameter $C\ensuremath{\equiv}{g}^{2}/(\ensuremath{\gamma}\ensuremath{\kappa})>350$.

arXiv:1607.05413•Physical Review A•Sep 6, 2016•30 citations

Dissipative preparation of a steady three-dimensional entangled state via quantum-jump-based feedback

Li Chen, Hong‐Fu Wang, Shou Zhang

A robust and scalable scheme to generate a steady three-dimensional entangled state for a V-type atom and a Λ-type atom trapped in a strongly dissipative bimodal cavity is proposed by direct feedback control based on quantum-jump detection. The robustness of this scheme reflects in the insensitivity to detection inefficiencies and the strong ability against the parameter fluctuations in the feedback, driving, and coupling strengths. The influence of atomic spontaneous emission can be suppressed by using the local feedback control. The scalability is ensured that N -dimensional entangled states of two atoms can be deterministically generated.

Chinese Physics B•Mar 1, 2014•2 citations

Effect of feedback control on the dynamics of quantum discord with and without the rotating-wave approximation

Jun-Qing Cheng, Wei Wu, Jing‐Bo Xu

We investigate the effect of quantum-jump-based feedback on the dynamics of quantum discord for two noninteracting two-level atoms coupled to a single mode of the cavity field with and without the rotating-wave approximation. It is found that the counterrotating terms can be helpful for generating steady states, and the value of steady-state quantum discord can be increased to approach 1 in the long-time limit by feedback controls. Furthermore, we also explore the influence of the time evolutions of mean excitation number in total systems and atomic subsystems on the quantum correlations and show that the enhancement of mean excitation number in atomic subsystems by feedback controls leads to the high value of steady-state quantum discord.

Journal of the Optical Society of America B•Mar 1, 2017•2 citations
We propose a theoretical scheme to enhance quantum coherence and obtain steady-state coherence by combining quantum feedback control and noise-assisted preparation. We investigate the effects of quantum-jump-based feedback control and noise field on the quantum coherence and excited-state population between two atoms inside an optical cavity where a noise field drives one, and the other is under quantum feedback control. It is found that steady quantum coherence can be achieved by adding an external noise field, and the quantum feedback can prolong the coherence time with partial suppression of the spontaneous emission of atoms. In addition, we study the influence of the joint action of quantum feedback and noise-assisted preparation on quantum coherence and show that the combined action of feedback control and noise-assisted preparation is more effective in enhancing steady coherence. The findings of our research offer some general guidelines for improving the steady-state coherence of coupled qubit systems and have the potential to be applied in the realm of quantum information technology.
We describe how feedback methods can be implemented to produce and stabilize entangled states of two atoms inside a cavity. Feedback control is used to engineer an effective environment dynamics, such that the entangled state to be protected is a steady state of the system. The control strategy is therefore robust with respect to external noises and fundamental decoherence sources, as spontaneous emission, for example. We also show that the scheme is mostly insensitive to practical imperfections, as detection inefficiencies and laser fluctuations.
We propose a theoretical method to enhance the coherent dipole coupling between two atoms in an optical cavity via parametrically squeezing the cavity mode. In the present scheme, conditions for coherent coupling are derived in detail and diverse dynamics of the system can be obtained by regulating system parameters. In the presence of environmental noise, an auxiliary squeezed field is employed to suppress and even completely eliminate the additional noise induced by squeezing. In addition, we demonstrate that our scheme enables the effective suppression of atomic spontaneous emission. The results in our investigation could be used for diverse applications in quantum technologies.
We study a physical system for creation of quantum correlations by quantum feedback control. The system is composed of two three-level atoms, each of which interacts with one of two coupled cavities. By appropriately choosing the feedback strength, we show that an arbitrary initial state can be deterministically driven to a steady-state that has a nonzero quantum discord or entanglement. It is also found that the effect of atomic spontaneous emission on quantum correlations is suppressed efficiently by increasing the frequency detuning.
We propose an experimentally feasible scheme for dissipative preparation of a tripartite entangled state with atoms separately trapped in an array of three coupled cavities. The combination of coherent driving fields and quantum-jump-based feedback control will drive the system into a nonequilibrium steady state, which has a nearly perfect overlap with the genuine three-atom singlet state. Different control strategies are investigated and the corresponding optimal parameters are confirmed. Moreover, the fidelity of the target state is insensitive to detection inefficiencies, and it exceeds 90% for a wide range of decoherence parameters as long as the single-atom cooperativity parameter $C\ensuremath{\equiv}{g}^{2}/(\ensuremath{\gamma}\ensuremath{\kappa})>350$.
A robust and scalable scheme to generate a steady three-dimensional entangled state for a V-type atom and a Λ-type atom trapped in a strongly dissipative bimodal cavity is proposed by direct feedback control based on quantum-jump detection. The robustness of this scheme reflects in the insensitivity to detection inefficiencies and the strong ability against the parameter fluctuations in the feedback, driving, and coupling strengths. The influence of atomic spontaneous emission can be suppressed by using the local feedback control. The scalability is ensured that N -dimensional entangled states of two atoms can be deterministically generated.
We investigate the effect of quantum-jump-based feedback on the dynamics of quantum discord for two noninteracting two-level atoms coupled to a single mode of the cavity field with and without the rotating-wave approximation. It is found that the counterrotating terms can be helpful for generating steady states, and the value of steady-state quantum discord can be increased to approach 1 in the long-time limit by feedback controls. Furthermore, we also explore the influence of the time evolutions of mean excitation number in total systems and atomic subsystems on the quantum correlations and show that the enhancement of mean excitation number in atomic subsystems by feedback controls leads to the high value of steady-state quantum discord.