Controllable Quantum Entanglement and One‐Way Steering in a Dual‐Cavity‐Magnon System

• Published in: Annalen der Physik 2024-11
• Main Authors: Zuo, Chun‐Yu, Qian, Rui‐Hao, Wu, Wen‐Bin, Tao, Yu, Xu, Ye‐Jun
• Format: Article
• Language: English
• ISSN: 0003-3804; 1521-3889
• DOI: 10.1002/andp.202400251

The quantum entanglement and the one‐way quantum steering in cavity magnonic system composed of a yttrium iron garnet (YIG) sphere and two microwave cavities, one of which is driven by a two‐photon drive field, are studied. Bipartite entanglement, tripartite entanglement, and steering can be achieved under the four‐wave mixing process. It is shown that the degree of entanglement and the direction of one‐way steering can be manipulated not only by designing the dissipation ratio between the two cavity modes but also by regulating the coherent coupling strength ratio between the two cavity modes and the magnon mode. It is found that the direction of steering is associated with the populations of the two cavity modes, meaning that the mode with a greater population always dominates the steering direction. Especially, the transfer between cavity–magnon entanglement and cavity–cavity entanglement can be realized by adjusting the coupling strengths. The findings provide a practical method for coherently manipulating entanglement and one‐way steering in cavity–magnon system.