2021/03/31 by Hong Xie, Zhigao Shi, Zhi-Gao Shi +6
Computer Science · Physics and Astronomy · #Bell state #Bell test experiments #Bell's theorem #Computer science #Coupling (piping) #Ferromagnetism #Laser #Magnon #Mechanical and Optical Resonators #Mode (computer interface) #Optical cavity #Optics #Photon #Photon entanglement #Physics #Pulse (music) #Quantum #Quantum Information and Cryptography #Quantum entanglement #Quantum mechanics #Quantum optics and atomic interactions #quant-ph
paper · pdf · doi:10.1103/physreva.105.023701
openalex publication_date 2022/02/01 · arxiv created 2022/02/06 · arxiv updated 2022/02/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a proposal to test the Bell inequality in the emerging field of cavity optomagnonics, where a sphere of ferromagnetic crystal supports two optical whispering gallery modes and one magnon mode. The two optical modes are driven by two laser pulses, respectively. Entanglement between the magnon mode and one of the two optical modes will be generated by the first pulse, and the state of the magnon mode is subsequently mapped into another optical mode via the second pulse. Hence correlated photon-photon pairs are created out of the cavity. A Bell test can be implemented by using these pairs, which enables us to test the local hidden-variable models at macroscopic scales. Our results show that a significant violation of the Bell inequality can be obtained in the weak-coupling regime. The violation of the Bell inequality not only verifies the entanglement between magnons and photons, but also implies that cavity optomagnonics is a promising platform for quantum information processing tasks.