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

Physical Review Research

Bistability of squeezing and entanglement in cavity magnonics

Zhi‐Bo Yang, Hua Jin, Jing-Wen Jin, Jian-Yu Liu, Hongyu Liu, Rong‐Can Yang

Published May 18, 2021• 79 citations
Publisher

Abstract

We demonstrate how magnon Kerr nonlinearity creates bistability of quantum states when the magnon mode is strongly driven by a microwave field in a nonlinear cavity magnonic system.Numerical simulation results with experimentally feasible parameters show that the method where the system is driven far from equilibrium is a reliable way to achieve squeezed states for magnons and photons and to carry out magnon-photon entanglement, revealing mysterious phenomena of bistability.In addition, the Kittel mode can jump from one state to another one near two switching points, thus achieving the hysteresis loop phenomenon.Our results indicate that bistable quantum states could provide a way to study macroscopic quantum bistable phenomena in nonlinear systems and also can be found in broad applications in magnetic spintronics.

DOI
10.1103/physrevresearch.3.023126

Related papers

Multistability of quantum entanglement and squeezing in nonlinear cavity magnonic systems

Jian-Gong Wang, Qi Guo

We focus on the multistability of quantum states in a nonlinear cavity magnonic system based on the cooperative effect of the magnon Kerr nonlinearity and the photon Kerr nonlinearity. Under experimentally feasible parameters, we first verify the multistability of magnon frequency shifts induced by the two nonlinearities by solving the classical mean value equations of the system. Then the multistability of the entangled state and squeezed state in the nonlinear system is revealed by investigating the quantum dynamics of the system fluctuations. By comparison, it is found that the multistable parameter regions for the classical states are exactly the same as those for the quantum states. We also explore the role of the system dissipations in the emergence of multistability, and the numerical results show that the multistable parameter regions will progressively shrink with the increase of the dissipations. These findings are meaningful for the study of nonlinear quantum effects in hybrid systems and may have potential applications in quantum information processing, precision measurement, and multifunctional quantum devices.

Optics Express•Mar 4, 2026•1 citation

Squeezed driving induced entanglement and squeezing among cavity modes and magnon mode in a magnon-cavity QED system

Ying Zhou, Jingping Xu, Shuangyuan Xie +1 more

We propose a scheme to generate entanglement between two cavity modes and squeeze magnon mode in a magnon-cavity QED system, where the two microwave cavity modes are coupled with a massive yttrium iron garnet (YIG) sphere through magnetic dipole interaction. The nonlinearity used in our system originates from a squeezed driving via parametric down-conversion process, which is the reason to cause entanglement and squeezing. By using the mean field approximation and employing experimentally feasible parameters, we demonstrate that the system shows zero entanglement and squeezing without squeezed driving. Meanwhile, our QED system denotes that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode via magnon-cavity coupling interaction, and then the two cavity modes get entangled. A genuinely tripartite entangled state is formed. We also show that magnon mode can be prepared in a squeezed state via magnon-cavity beam-splitter interaction, which is as a result of the squeezed field. Moreover, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain coefficient of squeezed driving. Our results denote that magnon-cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new method to photon-photon entanglement and magnon squeezing.

arXiv:2201.09154•Jan 23, 2022•0 citations

Generation of squeezed states of magnons and photons based on the Kerr effect in cavity-magnon hybrid system

Cheng‐Hua Bai, Suying Bai

Abstract Based on the magnon Kerr effect, we show how to generate quantum squeezed states of magnons and photons in the cavity–magnon hybrid system. We find that the squeezing of magnons can be successfully induced by the magnon nonlinearity and the larger two-magnon effect strength will be beneficial to achieving the stronger squeezing of magnon. Resorting to the beam-splitter interaction between the magnons and photons, we further show that the squeezing of photons can be also effectively achieved. By properly choosing the system parameters, we demonstrate that the desired direction of the generated squeezing both for magnons and photons can be flexibly switched between orthogonal directions. Our scheme provides an alternative manipulation method to explore the quantum phenomena with nonlinear effects and also has significant potential applications in quantum precision measurement.

Chinese Physics B•Feb 27, 2026•2 citations

Magneton bistability in quantum dot-double cavity optomechanical coupling system

Yanchao She, Xu Min-Qi, Wenya FENG +2 more

Magnons, as quasiparticles arising from spin wave excitations in magnetic materials, have demonstrated significant application potential in quantum information technology, spintronics, and microwave engineering in recent years. The cavity magnon optomechanical system, serving as a key platform for investigating magneto-optical interactions, has advanced the exploration of nonlinear dynamical behaviors and the innovative design of quantum devices through strong coupling between magnons, photons, and phonons. However, traditional single-cavity systems face limitations in terms of tunability, long-range interactions, and nonlinear enhancement, making them insufficient for complex quantum control requirements. In recent years, dual-cavity systems have become a research hotspot due to their multidimensional control capabilities achieved through inter-cavity coupling, such as photon mode splitting and enhanced nonlinear Kerr effects. Meanwhile, semiconductor quantum dots, provide a novel pathway for regulating magnon dynamics due to their tunable nonlinear response characteristics. In this work, we construct a novel coupled quantum system by integrating quantum dots and a dual-cavity architecture, and investigate the bistable phenomena under both forward and backward driving field inputs. By comparing the third-order nonlinear equations governing magnon populations in the two scenarios, we derive the impedance matching condition. When this condition is satisfied, the magnon responses induced by forward driving field and backward driving field are identical. Conversely, under impedance mismatch, the magnon responses exhibit different behaviors. Specifically, when the impedance matching condition is violated, the dual-cavity magnon optomechanical system incorporating three-level quantum dot molecules exhibits a lower bistability threshold than its counterpart without quantum dots. This allows for a transition from low steady state to high steady state while reducing the driving field strength, thereby achieving switching functionality at lower input power. Furthermore, we establish a multiparameter cooperative control model, revealing a three-dimensional parameter space formed by tunneling coupling, cavity-quantum dot coupling, and inter-cavity coupling. By adjusting these coupling strengths, the bistability threshold and hysteresis loop width can be effectively controlled, thereby modulating the driving field intensity required for bistability. This system is expected to experimentally observe the magnonic bistability through the vector network analyzer-based detection of abrupt changes in transmission or absorption windows in reflection spectra. Such capabilities can advance data signal transmission, switching devices, and memory technologies, and has the potential to serve as components of large-scale quantum information processing units. Additionally, this research may find important applications in the field of magnetic spintronics.

Acta Physica Sinica•Jan 1, 2025•0 citations

Entangling two cavity modes and squeezing magnon mode via parametric down-conversion

Ying Zhou, Jingping Xu, Shuangyuan Xie

Abstract A scheme to entangle two cavity modes and squeeze magnon mode in a magnon–cavity QED system is presented, where the two microwave cavity modes are coupled to a massive yttrium iron garnet sphere. The nonlinearity used in our system originates from parametric down-conversion. By using the mean field approximation and employing experimentally feasible parameters, we indicate that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode, and then the two cavity modes get entangled. Meanwhile, the magnon mode is squeezed in our QED system. Furthermore, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain. Our results denote that magnon–cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new approach to photon–photon entanglement and magnon squeezing.

Journal of Physics B Atomic Molecular and Optical Physics•Aug 31, 2022•5 citations

Steady-squeezed-state generation via Kerr nonlinearity in cavity magnonics system

Jia-Xin Wang, Qi Guo, Yuchi Zhang +2 more

Abstract We propose a scheme to generate squeezed states in a cross-shaped cavity magnonics system by Kerr effect originating from the magnetocrystalline anisotropy. The system consists of two microwave cavities and a yttrium iron garnet sphere supporting a magnon mode embodying the collective spin motion, and each cavity mode is coupled with the magnon mode through the magnetic-dipole interaction. It is demonstrated that simultaneous squeezing of the two microwave cavity modes and the magnon mode can be achieved due to Kerr nonlinearity, and the squeezing of the magnon mode can break the 3 dB limit. By utilizing a Bogoliubov transformation, a new perspective on the underlying physical mechanism for the generation of the squeezing using Kerr nonlinearity is provided. Moreover, we also demonstrate the strong robustness of the magnon mode’s squeezing against the system dissipation and environmental temperature. The present scheme provides a promising platform for quantum information processing, holding significant implications for quantum metrology and precision measurement.

Journal of Physics A Mathematical and Theoretical•May 28, 2025•6 citations
We demonstrate how magnon Kerr nonlinearity creates bistability of quantum states when the magnon mode is strongly driven by a microwave field in a nonlinear cavity magnonic system.Numerical simulation results with experimentally feasible parameters show that the method where the system is driven far from equilibrium is a reliable way to achieve squeezed states for magnons and photons and to carry out magnon-photon entanglement, revealing mysterious phenomena of bistability.In addition, the Kittel mode can jump from one state to another one near two switching points, thus achieving the hysteresis loop phenomenon.Our results indicate that bistable quantum states could provide a way to study macroscopic quantum bistable phenomena in nonlinear systems and also can be found in broad applications in magnetic spintronics.
We focus on the multistability of quantum states in a nonlinear cavity magnonic system based on the cooperative effect of the magnon Kerr nonlinearity and the photon Kerr nonlinearity. Under experimentally feasible parameters, we first verify the multistability of magnon frequency shifts induced by the two nonlinearities by solving the classical mean value equations of the system. Then the multistability of the entangled state and squeezed state in the nonlinear system is revealed by investigating the quantum dynamics of the system fluctuations. By comparison, it is found that the multistable parameter regions for the classical states are exactly the same as those for the quantum states. We also explore the role of the system dissipations in the emergence of multistability, and the numerical results show that the multistable parameter regions will progressively shrink with the increase of the dissipations. These findings are meaningful for the study of nonlinear quantum effects in hybrid systems and may have potential applications in quantum information processing, precision measurement, and multifunctional quantum devices.
We propose a scheme to generate entanglement between two cavity modes and squeeze magnon mode in a magnon-cavity QED system, where the two microwave cavity modes are coupled with a massive yttrium iron garnet (YIG) sphere through magnetic dipole interaction. The nonlinearity used in our system originates from a squeezed driving via parametric down-conversion process, which is the reason to cause entanglement and squeezing. By using the mean field approximation and employing experimentally feasible parameters, we demonstrate that the system shows zero entanglement and squeezing without squeezed driving. Meanwhile, our QED system denotes that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode via magnon-cavity coupling interaction, and then the two cavity modes get entangled. A genuinely tripartite entangled state is formed. We also show that magnon mode can be prepared in a squeezed state via magnon-cavity beam-splitter interaction, which is as a result of the squeezed field. Moreover, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain coefficient of squeezed driving. Our results denote that magnon-cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new method to photon-photon entanglement and magnon squeezing.
Abstract Based on the magnon Kerr effect, we show how to generate quantum squeezed states of magnons and photons in the cavity–magnon hybrid system. We find that the squeezing of magnons can be successfully induced by the magnon nonlinearity and the larger two-magnon effect strength will be beneficial to achieving the stronger squeezing of magnon. Resorting to the beam-splitter interaction between the magnons and photons, we further show that the squeezing of photons can be also effectively achieved. By properly choosing the system parameters, we demonstrate that the desired direction of the generated squeezing both for magnons and photons can be flexibly switched between orthogonal directions. Our scheme provides an alternative manipulation method to explore the quantum phenomena with nonlinear effects and also has significant potential applications in quantum precision measurement.
Magnons, as quasiparticles arising from spin wave excitations in magnetic materials, have demonstrated significant application potential in quantum information technology, spintronics, and microwave engineering in recent years. The cavity magnon optomechanical system, serving as a key platform for investigating magneto-optical interactions, has advanced the exploration of nonlinear dynamical behaviors and the innovative design of quantum devices through strong coupling between magnons, photons, and phonons. However, traditional single-cavity systems face limitations in terms of tunability, long-range interactions, and nonlinear enhancement, making them insufficient for complex quantum control requirements. In recent years, dual-cavity systems have become a research hotspot due to their multidimensional control capabilities achieved through inter-cavity coupling, such as photon mode splitting and enhanced nonlinear Kerr effects. Meanwhile, semiconductor quantum dots, provide a novel pathway for regulating magnon dynamics due to their tunable nonlinear response characteristics. In this work, we construct a novel coupled quantum system by integrating quantum dots and a dual-cavity architecture, and investigate the bistable phenomena under both forward and backward driving field inputs. By comparing the third-order nonlinear equations governing magnon populations in the two scenarios, we derive the impedance matching condition. When this condition is satisfied, the magnon responses induced by forward driving field and backward driving field are identical. Conversely, under impedance mismatch, the magnon responses exhibit different behaviors. Specifically, when the impedance matching condition is violated, the dual-cavity magnon optomechanical system incorporating three-level quantum dot molecules exhibits a lower bistability threshold than its counterpart without quantum dots. This allows for a transition from low steady state to high steady state while reducing the driving field strength, thereby achieving switching functionality at lower input power. Furthermore, we establish a multiparameter cooperative control model, revealing a three-dimensional parameter space formed by tunneling coupling, cavity-quantum dot coupling, and inter-cavity coupling. By adjusting these coupling strengths, the bistability threshold and hysteresis loop width can be effectively controlled, thereby modulating the driving field intensity required for bistability. This system is expected to experimentally observe the magnonic bistability through the vector network analyzer-based detection of abrupt changes in transmission or absorption windows in reflection spectra. Such capabilities can advance data signal transmission, switching devices, and memory technologies, and has the potential to serve as components of large-scale quantum information processing units. Additionally, this research may find important applications in the field of magnetic spintronics.
Abstract A scheme to entangle two cavity modes and squeeze magnon mode in a magnon–cavity QED system is presented, where the two microwave cavity modes are coupled to a massive yttrium iron garnet sphere. The nonlinearity used in our system originates from parametric down-conversion. By using the mean field approximation and employing experimentally feasible parameters, we indicate that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode, and then the two cavity modes get entangled. Meanwhile, the magnon mode is squeezed in our QED system. Furthermore, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain. Our results denote that magnon–cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new approach to photon–photon entanglement and magnon squeezing.
Abstract We propose a scheme to generate squeezed states in a cross-shaped cavity magnonics system by Kerr effect originating from the magnetocrystalline anisotropy. The system consists of two microwave cavities and a yttrium iron garnet sphere supporting a magnon mode embodying the collective spin motion, and each cavity mode is coupled with the magnon mode through the magnetic-dipole interaction. It is demonstrated that simultaneous squeezing of the two microwave cavity modes and the magnon mode can be achieved due to Kerr nonlinearity, and the squeezing of the magnon mode can break the 3 dB limit. By utilizing a Bogoliubov transformation, a new perspective on the underlying physical mechanism for the generation of the squeezing using Kerr nonlinearity is provided. Moreover, we also demonstrate the strong robustness of the magnon mode’s squeezing against the system dissipation and environmental temperature. The present scheme provides a promising platform for quantum information processing, holding significant implications for quantum metrology and precision measurement.