Entanglement and quantum steering in a hybrid quadpartite system

Abstract

We consider a quadpartite hybrid system that incorporates a microwave cavity, a yttrium-iron-garnet (YIG) magEntanglement and quantumnetic sphere resonator, a mechanical resonator, and an LC electrical resonator. The entanglement and the quantum steering properties of this quadpartite system are thoroughly investigated by considering practical parameters. The microwave cavity mode is directly coupled to the magnon, mechanical, and electrical modes via Kittel magnetostatics, radiation pressure, and adjustable capacitance of the LC configuration, respectively. We demonstrate tripartite entanglement among different modes, including indirectly coupled modes (such as magnon entanglement with mechanical and LC electrical modes) for operating temperatures up to 2 K. Furthermore, we observe the presence of asymmetric one-way steering, revealing that the mechanical oscillator and the LC resonant modes can steer the indirectly coupled magnon mode (yet in one direction while steering is not possible in the backward direction). The integration of the four interacting modes provides a variety of controlling degrees of freedom and makes the proposed quadpartite system an attractive approach for a wide range of applications, including data processing and communication, sensing, and quantum technologies. Keywords: Hybrid quantum systems, Magnons, Optoelectronics, Phonons