Remote magnon entanglement between two massive ferrimagnetic spheres via cavity optomagnonics

TL;DR

This paper proposes a method to entangle two large ferrimagnetic spheres using cavity optomagnonics, leveraging magnon-photon interactions to generate macroscopic quantum states in massive systems.

Contribution

It introduces a novel scheme for entangling two massive YIG spheres via cavity optomagnonics, utilizing asymmetry in Stokes and anti-Stokes scattering processes.

Findings

Entanglement of two 1mm YIG spheres demonstrated.

Utilizes Stokes and anti-Stokes scattering for entanglement generation and verification.

Shows cavity optomagnonics as a promising platform for macroscopic quantum states.

Abstract

Recent studies show that hybrid quantum systems based on magnonics provide a new and promising platform for generating macroscopic quantum states involving a large number of spins. Here we show how to entangle two magnon modes in two massive yttrium-iron-garnet (YIG) spheres using cavity optomagnonics, where magnons couple to high-quality optical whispering gallery modes supported by the YIG sphere. The spheres can be as large as 1 mm in diameter and each sphere contains more than $10^{18}$ spins. The proposal is based on the asymmetry of the Stokes and anti-Stokes sidebands generated by the magnon-induced Brillouin light scattering in cavity optomagnonics. This allows one to utilize the Stokes and anti-Stokes scattering process, respectively, for generating and verifying the entanglement. Our work indicates that cavity optomagnonics could be a promising system for preparing macroscopic quantum states.