Squeezed driving induced entanglement and squeezing among cavity modes and magnon mode in a magnon-cavity QED system

TL;DR

This paper proposes a scheme in a magnon-cavity QED system to generate entanglement between cavity modes and squeeze the magnon mode using squeezed driving, demonstrating feasible experimental parameters and potential for macroscopic quantum phenomena.

Contribution

It introduces a novel method to produce entanglement and squeezing in a magnon-cavity system via squeezed driving and magnon-cavity interactions, forming tripartite entangled states.

Findings

Entanglement transferred between cavity modes and magnon mode.

Magnon mode can be squeezed via beam-splitter interaction.

Entanglement and squeezing enhanced by increasing nonlinear gain.

Abstract

We propose a scheme to generate entanglement between two cavity modes and squeeze magnon mode in a magnon-cavity QED system, where the two microwave cavity modes are coupled with a massive yttrium iron garnet (YIG) sphere through magnetic dipole interaction. The nonlinearity used in our system originates from a squeezed driving via parametric down-conversion process, which is the reason to cause entanglement and squeezing. By using the mean field approximation and employing experimentally feasible parameters, we demonstrate that the system shows zero entanglement and squeezing without squeezed driving. Meanwhile, our QED system denotes that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode via magnon-cavity coupling interaction, and then the two cavity modes get entangled. A genuinely tripartite entangled state is formed. We also show that magnon mode can be prepared in a squeezed state via magnon-cavity beam-splitter interaction, which is as a result of the squeezed field. Moreover, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain coefficient of squeezed driving. Our results denote that magnon-cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new method to photon-photon entanglement and magnon squeezing.