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

Advanced Quantum Technologies

Nonreciprocal Entanglement in Spinning Cavity Magnomechanical System with Coherent Feedback Loop

Cheng‐Zhi Gao, Guoqing Liu, Nan Wang, Lin Yu, Ai‐Dong Zhu

Published Apr 8, 2025• 3 citations
Publisher

Abstract

Abstract A scheme is proposed for generating and enhancing stable nonreciprocal entanglement in a spinning cavity magnomechanical system. The key components of this scheme include a ferromagnetic yttrium iron garnet sphere and a whispering gallery mode resonator supporting two counter‐propagating modes. To further optimize the performance of the system, a coherent feedback loop is introduced to reinject the dissipated energy back into the system. This not only provides an additional coupling path for the system but also effectively avoids introducing additional noise caused by measurement. The design significantly enhances both bipartite entanglement and genuine tripartite entanglement. Meanwhile, by spinning the resonator, the cavity modes experience Fizeau drag due to the optical Sagnac effect, thereby achieving nonreciprocal entanglement, which is crucial for applications such as unidirectional quantum communication channels. Additionally, the research demonstrates that even in the presence of backscattering, the entangled state can still recover significantly, highlighting the robustness of entanglement under photon backscattering. This work provides an effective method to enhance and protect quantum resources and holds important application potential for applications in quantum information processing based on magnonics.

DOI
10.1002/qute.202500063

Related papers

Nonreciprocal magnon-photon-phonon entanglement in cavity magnomechanics

Subhadeep Chakraborty, Camelia Das

We propose a scheme to create nonreciprocal entanglement in a spinning cavity magnomechanical system. The setup comprises a whispering gallery mode resonator with two counterpropagating modes, simultaneously coupled to yttrium iron garnet. By spinning the resonator, the counterpropagating modes undergo an opposite Fizeau drag caused by the optical Sagnac effect. We show that in a spinning resonator, the cavity-magnon-phonon modes get entangled along a chosen direction while remaining fully uncorrelated in the other. The degree of nonreciprocity is determined by the drive detuning and the spinning velocity of the resonator. Our work provides a different route to achieve chiral control of quantum entanglement involving magnon-photon-phonon modes.

Physical Review A•Dec 6, 2023•47 citations

Nonreciprocal magnon-magnon entanglement in a spinning cavity-magnon system

Zhisheng Xu, Mengxue Li, Chunfang Sun +1 more

Cavity-magnon systems, combining magnons and photons, offer a versatile platform for studying quantum entanglement and advancing quantum information science. In this work, we propose a scheme for generating nonreciprocal magnon-magnon entanglement in a hybrid system consisting of two yttrium iron garnet spheres coupled to a spinning whispering-gallery-mode cavity. By leveraging the magnon Kerr nonlinearity and the Sagnac effect arising from the cavity rotation, we show that the entanglement can be substantially enhanced, and the resulting entanglement exhibits pronounced nonreciprocal characteristics. Furthermore, our scheme demonstrates that the entanglement remains robust against thermal noise and persists at bath temperatures up to 100 mK. This work underscores the potential of spinning cavity-magnon systems as a versatile platform for realizing nonreciprocal quantum devices and facilitating the development of quantum technologies.

quant-pharXiv:2605.14394•May 15, 2026•0 citations

Barnett effect boosted nonreciprocal entanglement and EPR-steering in magnomechanics in the presence of coherent feedback loop

Noura Chabar, Mohamed Amazioug

We propose an experimental scheme for enhancing entanglement, achieving asymmetric Einstein-Podolsky-Rosen (EPR) steering, and creating nonreciprocal quantum correlations within a hybrid system. This system integrates a yttrium iron garnet (YIG) sphere, which exhibits magnon-phonon coupling via magnetostriction, with a silica sphere featuring optomechanical whispering-gallery modes. By tuning the Barnett effect through the magnetic field direction, our system enables controllable asymmetric EPR steering and nonreciprocal entanglement between both directly and indirectly coupled modes. We demonstrate that adjusting the reflectivity of a beam splitter can boost stationary quantum steering and entanglement, effectively countering thermal noise. This approach allows for the generation of multipartite entanglement and both one-way and two-way steering. The proposed system is experimentally feasible and holds significant promise for various quantum information applications.

arXiv:2507.09590•Jul 13, 2025•0 citations

Nonreciprocal quantum coherence in spinning magnomechanical systems

Haoqi Zhang, Xianxin Shang, Qinghong Liao +2 more

We theoretically investigate the quantum coherence and its nonreciprocity in a cavity magnomechanical system composed of a spinning microwave resonant cavity and an yttrium iron garnet sphere. The optical Fizeau shift related to the driving direction of the microwave cavity is responsible for an important source of nonreciprocity in the stability of the system, which leads to the nonreciprocal quantum coherence. Remarkably, the quantum coherence of the mechanical motion mode can be greater than that of the microwave photon and the magnon modes, which describes a significant enhancement of the correlations of the system. We also analyze in detail the influence of the strength of the magnomechanical coupling, the Kerr nonlinearity, and the effective detunings on the quantum coherence. Our paper paves the way for optimizing the stability range of coupled systems and maintaining more reliable quantum coherence by designing and modulating the system parameters in cavity magnetomechanical systems.

Physical Review A•Jan 24, 2024•10 citations

Nonreciprocal Multipartite Entanglement in a two-cavity magnomechanical system

Rizwan Ahmed, Ali, Hazrat, Shehzad, Aamir +3 more

We propose a theoretical scheme for the generation of nonreciprocal multipartite entanglement in a two-mode cavity magnomechanical system, consisting of two cross-microwave (MW) cavities having a yttrium iron garnet (YIG) sphere, which is coupled through magnetic dipole interaction. Our results show that the self-Kerr effect of magnon can significantly enhance multipartite entanglement, which turns out to be nonreciprocal when the magnetic field is tuned along the crystallographic axis [110]. This is due to the frequency shift on the magnons (YIG sphere), which depends on the direction of the magnetic field. Interestingly, the degree of nonreciprocity of bipartite entanglements depends upon a careful optimal choice of system parameters like normalized cavity detunings, bipartite nonlinear index, self-Kerr coefficient, and effective magnomechanical coupling rate G. In addition to bipartite entanglement, we also present the idea of a bidirectional contrast ratio, which quantifies the nonreciprocity in tripartite entanglements. Our present theoretical proposal for nonreciprocity in multipartite entanglement may find applications in diverse engineering nonreciprocal devices

arXiv:2405.16221•May 25, 2024•0 citations

Entanglement Enhancement by the Synergistic Effect of Optical Parametric Amplification and Coherent Feedback in Cavity Magnonics

Guoqing Liu, Cheng‐Zhi Gao, Nan Wang +2 more

Abstract The scheme is proposed to enhance the entanglement in cavity‐magnonics system by exploiting the synergistic effects of an optical parametric amplifier (OPA) and coherent feedback. In the system, the two cavities are arranged in a cross‐shaped, with a yttrium iron garnet (YIG) sphere positioned near the intersection of the cross‐shaped cavities. By introducing coherent feedback, the energy dissipated by the horizontal cavity can be fed back into the vertical cavity, which can be compensated via OPA. The nonlinear gain of OPA and reflectivity of the coherent feedback play important roles in the dynamics of the system and enable enhancement of both bipartite and tripartite entanglement as compared to the system without OPA and coherent feedback. The robustness of entanglement against environment temperature can also be greatly improved. Moreover, in the system that possesses a symmetrical structure but demonstrates asymmetric energy flow, controllable one‐way steering can be realized through the precise adjustment of specific parameters within the system. The scheme offers a novel approach to realize high‐quality entanglement resources and holds potential applications in quantum information processing and quantum communication.

Advanced Quantum Technologies•Jun 10, 2025•1 citation
Abstract A scheme is proposed for generating and enhancing stable nonreciprocal entanglement in a spinning cavity magnomechanical system. The key components of this scheme include a ferromagnetic yttrium iron garnet sphere and a whispering gallery mode resonator supporting two counter‐propagating modes. To further optimize the performance of the system, a coherent feedback loop is introduced to reinject the dissipated energy back into the system. This not only provides an additional coupling path for the system but also effectively avoids introducing additional noise caused by measurement. The design significantly enhances both bipartite entanglement and genuine tripartite entanglement. Meanwhile, by spinning the resonator, the cavity modes experience Fizeau drag due to the optical Sagnac effect, thereby achieving nonreciprocal entanglement, which is crucial for applications such as unidirectional quantum communication channels. Additionally, the research demonstrates that even in the presence of backscattering, the entangled state can still recover significantly, highlighting the robustness of entanglement under photon backscattering. This work provides an effective method to enhance and protect quantum resources and holds important application potential for applications in quantum information processing based on magnonics.
We propose a scheme to create nonreciprocal entanglement in a spinning cavity magnomechanical system. The setup comprises a whispering gallery mode resonator with two counterpropagating modes, simultaneously coupled to yttrium iron garnet. By spinning the resonator, the counterpropagating modes undergo an opposite Fizeau drag caused by the optical Sagnac effect. We show that in a spinning resonator, the cavity-magnon-phonon modes get entangled along a chosen direction while remaining fully uncorrelated in the other. The degree of nonreciprocity is determined by the drive detuning and the spinning velocity of the resonator. Our work provides a different route to achieve chiral control of quantum entanglement involving magnon-photon-phonon modes.
Cavity-magnon systems, combining magnons and photons, offer a versatile platform for studying quantum entanglement and advancing quantum information science. In this work, we propose a scheme for generating nonreciprocal magnon-magnon entanglement in a hybrid system consisting of two yttrium iron garnet spheres coupled to a spinning whispering-gallery-mode cavity. By leveraging the magnon Kerr nonlinearity and the Sagnac effect arising from the cavity rotation, we show that the entanglement can be substantially enhanced, and the resulting entanglement exhibits pronounced nonreciprocal characteristics. Furthermore, our scheme demonstrates that the entanglement remains robust against thermal noise and persists at bath temperatures up to 100 mK. This work underscores the potential of spinning cavity-magnon systems as a versatile platform for realizing nonreciprocal quantum devices and facilitating the development of quantum technologies.
We propose an experimental scheme for enhancing entanglement, achieving asymmetric Einstein-Podolsky-Rosen (EPR) steering, and creating nonreciprocal quantum correlations within a hybrid system. This system integrates a yttrium iron garnet (YIG) sphere, which exhibits magnon-phonon coupling via magnetostriction, with a silica sphere featuring optomechanical whispering-gallery modes. By tuning the Barnett effect through the magnetic field direction, our system enables controllable asymmetric EPR steering and nonreciprocal entanglement between both directly and indirectly coupled modes. We demonstrate that adjusting the reflectivity of a beam splitter can boost stationary quantum steering and entanglement, effectively countering thermal noise. This approach allows for the generation of multipartite entanglement and both one-way and two-way steering. The proposed system is experimentally feasible and holds significant promise for various quantum information applications.
We theoretically investigate the quantum coherence and its nonreciprocity in a cavity magnomechanical system composed of a spinning microwave resonant cavity and an yttrium iron garnet sphere. The optical Fizeau shift related to the driving direction of the microwave cavity is responsible for an important source of nonreciprocity in the stability of the system, which leads to the nonreciprocal quantum coherence. Remarkably, the quantum coherence of the mechanical motion mode can be greater than that of the microwave photon and the magnon modes, which describes a significant enhancement of the correlations of the system. We also analyze in detail the influence of the strength of the magnomechanical coupling, the Kerr nonlinearity, and the effective detunings on the quantum coherence. Our paper paves the way for optimizing the stability range of coupled systems and maintaining more reliable quantum coherence by designing and modulating the system parameters in cavity magnetomechanical systems.
We propose a theoretical scheme for the generation of nonreciprocal multipartite entanglement in a two-mode cavity magnomechanical system, consisting of two cross-microwave (MW) cavities having a yttrium iron garnet (YIG) sphere, which is coupled through magnetic dipole interaction. Our results show that the self-Kerr effect of magnon can significantly enhance multipartite entanglement, which turns out to be nonreciprocal when the magnetic field is tuned along the crystallographic axis [110]. This is due to the frequency shift on the magnons (YIG sphere), which depends on the direction of the magnetic field. Interestingly, the degree of nonreciprocity of bipartite entanglements depends upon a careful optimal choice of system parameters like normalized cavity detunings, bipartite nonlinear index, self-Kerr coefficient, and effective magnomechanical coupling rate G. In addition to bipartite entanglement, we also present the idea of a bidirectional contrast ratio, which quantifies the nonreciprocity in tripartite entanglements. Our present theoretical proposal for nonreciprocity in multipartite entanglement may find applications in diverse engineering nonreciprocal devices
Abstract The scheme is proposed to enhance the entanglement in cavity‐magnonics system by exploiting the synergistic effects of an optical parametric amplifier (OPA) and coherent feedback. In the system, the two cavities are arranged in a cross‐shaped, with a yttrium iron garnet (YIG) sphere positioned near the intersection of the cross‐shaped cavities. By introducing coherent feedback, the energy dissipated by the horizontal cavity can be fed back into the vertical cavity, which can be compensated via OPA. The nonlinear gain of OPA and reflectivity of the coherent feedback play important roles in the dynamics of the system and enable enhancement of both bipartite and tripartite entanglement as compared to the system without OPA and coherent feedback. The robustness of entanglement against environment temperature can also be greatly improved. Moreover, in the system that possesses a symmetrical structure but demonstrates asymmetric energy flow, controllable one‐way steering can be realized through the precise adjustment of specific parameters within the system. The scheme offers a novel approach to realize high‐quality entanglement resources and holds potential applications in quantum information processing and quantum communication.