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arXiv · 2408.05638

Asymmetric EPR Steering in a Cavity-Magnon System Generated by a Squeezed Vacuum Field and an Optical Parametric Amplifier

Abstract

We investigate a cavity-magnon system with two magnon modes coupled to a common cavity microwave field. The cavity is integrated with an optical parametric amplifier (OPA) and driven by a squeezed vacuum field. The introduction of the OPA and the squeezed vacuum field induce squeezing in the cavity mode, which is transferred to the magnon modes through magnetic dipole interactions. Our findings demonstrate that enhancing the OPA gain and the squeezing parameter significantly enhances the quantum entanglement and the Einstein-Podolsky-Rosen (EPR) steering. Furthermore, the photon-magnon coupling strength can be adjusted to control the directionality of EPR steering, offering a mechanism for achieving one-way EPR steering under specific conditions. This control is fine-tuned by varying system parameters, thereby providing a robust platform for steering in the presence of thermal noise. Our findings advance the understanding of macroscopic quantum correlations and hold promising implications for quantum information processing, particularly in generating, manipulating, and enhancing quantum steering phenomena. This practical aspect of our research will inspire hope for future applications in the field of quantum information.

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Abdelkader Hidki, Noureddine Benrass, Abderrahim Lakhfif, Mostafa Nassik. 2024-08-10. Asymmetric EPR Steering in a Cavity-Magnon System Generated by a Squeezed Vacuum Field and an Optical Parametric Amplifier. https://arxiv.org/abs/2408.05638

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