Quantum entanglement is a fundamental phenomenon in quantum information science and a crucial resource for quantum technologies such as precision sensing, secure communication, and computation. In hybrid cavity magno-optomechanical systems, entanglement among cavity photons, magnons, and phonons enables manipulation of quantum states across different modes via radiation pressure-based light-matter interaction. We propose a hybrid optomechanical cavity-magnonic setup with Yttrium iron garnet (YIG) sphere allowing magnons to couple with photons via magnetic-dipole interaction. The system also uses optomechanical and electrostatic interactions to entangle cavity photons and mechanical resonators. We focus on how the magnon nonlinear Kerr effect and varying coupling strengths influence entanglement dynamics. By analysing nonlinear effects alongside other coupling parameters, we identify optimal conditions for initiating and sustaining robust entanglement between the motional modes (phonons) of two Coulomb-coupled mechanical resonators. Our model predicts that adding Coulomb interaction and magnon coupling enhances the degree and tunability of entanglement, making it more resilient to thermal baths at 3 K. This study addresses how to optimize and sustain phonon-phonon entanglement in complex hybrid quantum systems. These findings offer insights relevant to developing quantum memories for continuous variable quantum information processing and other quantum technologies.
Quantum entanglement is a fundamental phenomenon in quantum information science and a crucial resource for quantum technologies such as precision sensing, secure communication, and computation. In hybrid cavity magno-optomechanical systems, entanglement among cavity photons, magnons, and phonons enables manipulation of quantum states across different modes via radiation pressure-based light-matter interaction. We propose a hybrid optomechanical cavity-magnonic setup with Yttrium iron garnet (YIG) sphere allowing magnons to couple with photons via magnetic-dipole interaction. The system also uses optomechanical and electrostatic interactions to entangle cavity photons and mechanical resonators. We focus on how the magnon nonlinear Kerr effect and varying coupling strengths influence entanglement dynamics. By analysing nonlinear effects alongside other coupling parameters, we identify optimal conditions for initiating and sustaining robust entanglement between the motional modes (phonons) of two Coulomb-coupled mechanical resonators. Our model predicts that adding Coulomb interaction and magnon coupling enhances the degree and tunability of entanglement, making it more resilient to thermal baths at 3 K. This study addresses how to optimize and sustain phonon-phonon entanglement in complex hybrid quantum systems. These findings offer insights relevant to developing quantum memories for continuous variable quantum information processing and other quantum technologies.
In this work, we present a hybrid cavity opto-magnomechanical system to generate distant bipartite entanglement between different quantum carriers. Accordingly, the system consists of two cavity photons, a phonon of yttrium iron garnet (YIG), a magnon, and a phonon of membrane. Specifically, the two cavities are coupled through an optical fiber, and one of the optical cavities consists of a membrane coupled with the cavity photon through radiation pressure force. While the other cavity contains a YIG, the magnon mode connects to the cavity photon via magnetic dipole interaction and, simultaneously, couples to the mechanical resonator of the YIG through magnetostrictive interaction. We show that entanglement generation can be realized under indirectly coupled bipartitions for parameters and detunings within appropriate regimes. Furthermore, for various bipartitions, we also obtain appropriate cavity and magnon detuning values for a considerable remote entanglement. Moreover, the generation of distant bipartite entanglements and entanglement transfer between subsystems is predominantly influenced by the coupling strength. Remarkably, the distant bipartite entanglement is strongly contrary to the environmental temperature. Thus, optimizing the system’s parameters allows for the maximum possible entanglement between various quantum carriers. We believe our results could provide more stable bipartite entanglements and serve as a potential quantum interface to realize particularly long-range entanglement transfers.
Abstract We propose to realize bipartite and tripartite entanglements transfer in a cavity magnomechanical system consisting of a microwave cavity with an yttrium iron garnet (YIG) sphere and a silicon-nitride membrane in it. The initial magnon–YIG phonon entanglement and photon-membrane phonon entanglement caused by the magnetostrictive interaction and the optomechanical interaction can be effectively transferred to magnon–membrane phonon entanglement and photon–YIG phonon entanglement. Photon–magnon–YIG phonon and photon–magnon–membrane phonon entanglements can also be realized in the system. These two types of tripartite entanglements can be easily transferred from one type to the other by adjusting the detuning or dissipation ratio. Moreover, the bipartite and tripartite entanglements and their transfer are all robust against temperature. Furthermore, by introducing supermodes formed by the photon and magnon modes, we find that the entanglement between the two mechanical modes can be obtained under the condition of an extremely low temperature. And the effective detuning region of the YIG phonon-membrane phonon entanglement is complementary to the detuning regions of other bipartite entanglements. Our results indicate that the combination of cavity magnomechanical and optomechanical systems could provide more flexible controllability of bipartite and tripartite entanglements and their transfer and could serve as a potential quantum interface among microwave, magnon, and mechanical systems.
Generating multipartite entanglement is always a popular research field in quantum information processing and quantum optics. In this paper, we propose a scheme to realize all bipartite entanglements and the genuine tripartite entanglement among photon, magnon, and phonon modes in a cavity-magnomechanical system. The center-of-mass motion of a yttrium iron garnet sphere couples to the magnon and constitutes photon-magnon-phonon tripartite interaction. By modulating the detuning between the cavity (magnon) mode and the driven field, we can obtain the optimal photon-phonon entanglement or magnon-phonon entanglement. The genuine tripartite entanglement can be prepared through a suitable detuning. We compare the different entanglement cases with and without effective direct cavity-magnon coupling. The results indicate that the photon-magnon entanglement can be enhanced by the effective cavity-magnon coupling strength, and all bipartite entanglements show greater robustness against the thermal phonon number. This investigation should be useful for phonon-involved multipartite quantum information processing and quantum precision measurement.
In this work, we employ logarithmic negativity to rigorously investigate bipartite entanglements in a lossy cavity magnomechanical system incorporating both photon and magnon Kerr nonlinearities. The system comprises two optical cavity modes, two yttrium-iron-garnet (YIG) spheres, which support magnon and phonon modes, and two electromagnetic fields that drive the magnons. Through numerical simulations, we systematically examine the influence of significant parameters, including photon-magnon and phonon-magnon coupling strengths, dissipation rates, Kerr nonlinearities, environmental temperatures, and normalized detuning on the bipartite entanglements between distinct subsystems. Our findings reveal that the amounts of bipartite entanglements can be precisely tuned by optimizing these parameters. Specifically, increasing either dissipation or Kerr nonlinearity diminishes the maximum values of entanglement. Furthermore, when the magnomechanical coupling is stronger, the entanglement becomes more robust and can endure across a broader spectrum of temperatures. Moreover, the entanglement generated within the subsystems demonstrates remarkable robustness against environmental temperature. Additionally, the maximum survival temperature of bipartite entanglements varies across different entangled pairs, and can be effectively controlled by the optical-magnon coupling strength. Notably, entanglement between subsystems persists even at cryogenic temperatures.
Realizing a strong light-matter interaction via magnetic dipoles is of fundamental importance in physics, and a cavity magnonics system has provided a unique platform to achieve strong and even ultrastrong light-matter interaction. In this work, transparency induced by magnon-photon interactions in cavity quantum electrodynamics (QED) system coupling a yttrium-iron-garnet (YIG,Y3Fe5O12) (YIG) sphere has been investigated. The spectral separation reveals a linear relationship with the coupling strength, which might find applications in magnon dark state and magnon-based quantum information processing.
We propose an alternative scheme to achieve the cross-correlations between magnon and photon in a hybrid nonlinear system including two microwave cavities and one yttrium iron garnet (YIG) sphere, where two cavities nonlinearly interact and meanwhile one of cavities couples to magnon representing the collective excitation in YIG sphere via magnetic dipole interaction. Based on dispersive couplings between two cavities and between one cavity and magnon with the larger detunings, the nonlinear interaction occurs between the other cavity and magnon, which plays a crucial role in generating quantum correlations. By analyzing the second-order correlation functions via numerical simulations and analytical calculations, the remarkable nonclassical correlations are existent in such a system, where the magnon blockade and photon antibunching could be obtainable on demand. The scheme we present is focused on the magnon-photon cross-correlations in the weak coupling regime and relaxes the requirements of experimental conditions, which may have potential applications in quantum information processing in the hybrid system.