分类： 光学 >> 量子光学 提交时间： 2023-02-20
摘要： Entanglement is a holistic property of multipartite quantum systems, which is accompanied by the establishment of nonclassical correlations between subsystems. Most entanglement mechanisms can be described by a coherent interaction Hamiltonian, and entanglement develops over time. In other words, the generation of entanglement has a time arrow. Dissipative structure theory directs the evolving time arrow of a non-equilibrium system. By dissipating energy to the environment, the system establishes order out of randomness. This is also referred to as self-organization. Here, we explore a new mechanism to create entanglement, utilizing the wisdom of dissipative structure theory in quantum systems. The entanglement between subsystems can emerge via the dissipation-structured correlation. This method requires a non-equilibrium initial state and cooperative dissipation, which can be implemented in a variety of waveguide-coupled quantum systems.
分类： 光学 >> 量子光学 提交时间： 2023-02-19
摘要： Squeezed light finds many important applications in quantum information science and quantum metrology, and has been produced in a variety of physical systems involving optical nonlinear processes. Here, we show how a nonlinear magnetostrictive interaction in a ferrimagnet in cavity magnomechanics can be used to reduce quantum noise of the electromagnetic field. We show optimal parameter regimes where a substantial and stationary squeezing of the microwave output field can be achieved. The scheme can be realized within the reach of current technology in cavity electromagnonics and magnomechanics. Our work provides a new and practicable approach for producing squeezed vacuum states of electromagnetic fields, and may find promising applications in quantum information processing and quantum metrology.
分类： 光学 >> 量子光学 提交时间： 2023-02-19
摘要： Recent studies show that hybrid quantum systems based on magnonics provide a new and promising platform for generating macroscopic quantum states involving a large number of spins. Here we show how to entangle two magnon modes in two massive yttrium-iron-garnet (YIG) spheres using cavity optomagnonics, where magnons couple to high-quality optical whispering gallery modes supported by the YIG sphere. The spheres can be as large as 1 mm in diameter and each sphere contains more than $10^{18}$ spins. The proposal is based on the asymmetry of the Stokes and anti-Stokes sidebands generated by the magnon-induced Brillouin light scattering in cavity optomagnonics. This allows one to utilize the Stokes and anti-Stokes scattering process, respectively, for generating and verifying the entanglement. Our work indicates that cavity optomagnonics could be a promising system for preparing macroscopic quantum states.
分类： 光学 >> 量子光学 提交时间： 2023-02-19
摘要： We show how to prepare a steady-state entangled state between magnons and optical photons in an opto-magnomechanical configuration, where a mechanical vibration mode couples to a magnon mode in a ferrimagnet by the dispersive magnetostrictive interaction, and to an optical cavity by the radiation pressure. We find that, by appropriately driving the magnon mode and the cavity to simultaneously activate the magnomechanical Stokes and the optomechanical anti-Stokes scattering, a stationary optomagnonic entangled state can be created. We further show that, by activating the magnomechanical state-swap interaction and subsequently sending a weak red-detuned optical pulse to drive the cavity, the magnonic state can be read out in the cavity output field of the pulse via the mechanical transduction. The demonstrated entanglement and state-readout protocols in such a novel opto-magnomechanical configuration allow us to optically control, prepare, and read out quantum states of collective spin excitations in solids, and provide promising opportunities for the study of quantum magnonics, macroscopic quantum states, and magnonic quantum information processing.
分类： 光学 >> 量子光学 提交时间： 2023-02-19
摘要： We show how to prepare macroscopic entanglement between an atomic ensemble and a large number of magnons in a ferrimagnetic YIG crystal. Specifically, we adopt an opto-magnomechanical configuration where the magnetostriction-induced magnomechanical displacement couples to an optical cavity via radiation pressure, and the latter further couples to an ensemble of two-level atoms that are placed inside the cavity. We show that by properly driving the cavity and magnon modes, optomechanical entanglement is created which is further distributed to the atomic and magnonic systems, yielding stationary entanglement between atoms and magnons. The atom-magnon entanglement is a result of the combined effect of opto- and magnomechanical cooling and optomechanical parametric down-conversion interactions. A competition mechanism between two mechanical cooling channels is revealed. Our results indicate that the hybrid opto-magnomechanical system may become a promising system for preparing macroscopic quantum states involving magnons, photons, phonons and atoms.
点击量
待评议
点击量
下载量
评论
