Stationary optomagnonic entanglement and magnon-to-optics quantum state transfer via opto-magnomechanics

TL;DR

This paper proposes a method to generate and read out stationary entangled states between magnons and optical photons using an opto-magnomechanical system, enabling quantum control and information processing of solid-state spin excitations.

Contribution

It introduces a novel opto-magnomechanical setup for creating and detecting magnon-photon entanglement and quantum state transfer, advancing quantum magnonics.

Findings

Steady-state magnon-optical entanglement achieved

Quantum state transfer from magnons to optical fields demonstrated

Protocols for optical control and readout of magnon states developed

Abstract

We show how to prepare a steady-state entangled state between magnons and optical photons in an opto-magnomechanical configuration, where a mechanical vibration mode couples to a magnon mode in a ferrimagnet by the dispersive magnetostrictive interaction, and to an optical cavity by the radiation pressure. We find that, by appropriately driving the magnon mode and the cavity to simultaneously activate the magnomechanical Stokes and the optomechanical anti-Stokes scattering, a stationary optomagnonic entangled state can be created. We further show that, by activating the magnomechanical state-swap interaction and subsequently sending a weak red-detuned optical pulse to drive the cavity, the magnonic state can be read out in the cavity output field of the pulse via the mechanical transduction. The demonstrated entanglement and state-readout protocols in such a novel opto-magnomechanical configuration allow us to optically control, prepare, and read out quantum states of collective spin excitations in solids, and provide promising opportunities for the study of quantum magnonics, macroscopic quantum states, and magnonic quantum information processing.