Magnon-photon-phonon entanglement in cavity magnomechanics

TL;DR

This paper demonstrates how to generate and verify robust tripartite entanglement among magnons, cavity photons, and phonons in a cavity magnomechanical system, highlighting its potential for macroscopic quantum studies.

Contribution

It introduces a method to produce and analyze tripartite entanglement in a cavity magnomechanical system with specific optimal parameters.

Findings

Tripartite entanglement is achievable and robust against temperature.

Steady state of the system is genuinely tripartite entangled.

Optimal parameter regimes for entanglement are identified.

Abstract

We show how to generate tripartite entanglement in a cavity magnomechanical system which consists of magnons, cavity microwave photons, and phonons. The magnons are embodied by a collective motion of a large number of spins in a macroscopic ferrimagnet, and are driven directly by an electromagnetic field. The cavity photons and magnons are coupled via magnetic dipole interaction, and the magnons and phonons are coupled via magnetostrictive (radiation pressure-like) interaction. We show optimal parameter regimes for achieving the tripartite entanglement where magnons, cavity photons, and phonons are entangled with each other, and we further prove that the steady state of the system is a genuinely tripartite entangled state. The entanglement is robust against temperature. Our results indicate that cavity magnomechanical systems could provide a promising platform for the study of macroscopic quantum phenomena.