Cavity magnomechanics: from classical to quantum

Abstract

Hybrid quantum systems based on magnons in magnetic materials have made significant progress in the past decade. They are built based on the couplings of magnons with microwave photons, optical photons, vibration phonons, and superconducting qubits. In particular, the interactions among magnons, microwave cavity photons, and vibration phonons form the system of cavity magnomechanics (CMM), which lies in the interdisciplinary field of cavity QED, magnonics, quantum optics, and quantum information. Here, we review the experimental and theoretical progress of this emerging field. We first introduce the underlying theories of the magnomechanical coupling, and then some representative classical phenomena that have been experimentally observed, including magnomechanically induced transparency, magnomechanical dynamical backaction, magnon-phonon cross-Kerr nonlinearity, etc. We also discuss a number of theoretical proposals, which show the potential of the CMM system for preparing different kinds of quantum states of magnons, phonons, and photons, and hybrid systems combining magnomechanics and optomechanics and relevant quantum protocols based on them. Finally, we summarize this review and provide an outlook for the future research directions in this field.

Hierarchy of tripartite entanglement detection in a cavity magnomechanical system

“…Illustrated in figure 2, the system under consideration is a typical cavity magnomechanical system [44,[47][48][49][50], comprising of a microwave cavity and a macroscopic YIG sphere placed inside the cavity, which supports a magnon (spin wave) mode and a mechanical vibration mode. The Hamiltonian of the system reads [44,51] (h = 1): The magnon frequency ω m can be easily adjusted by altering the bias magnetic field H 0 via ω m = γ 0 H 0 , with the gyromagnetic ratio γ 0 /2π = 28 GHz/T. g mb denotes the bare coupling rate between the magnon and the mechanical mode and g ma is the cavity-magnon coupling rate, which can be (much) stronger than the cavity and magnon dissipation rates κ a and κ m [38][39][40].…”

Using magnons as a quantum technology platform: a perspective

“…Moreover, the exploration of tunable slow light within cavity magneto-mechanical systems [148], driven by magnetostrictive force, has expanded the field's scope, especially concerning information interconversion. Further, in the presence of strong hybridization between magnon and microwave photon modes and their high tunability, new features can emerge, including parametric amplification of magnons and phonons, triple-resonant photon-magnon-phonon coupling, phonon lasing, and magnon-induced dynamical backaction in a cavity magnomechanical system [149][150][151][152]. Additionally, the controlled resonant excitation of magnons through a signal-driving field, facilitated by another strong field via interference of excitation pathways, has enabled the development of a highly functional magnonic switch [153,154].…”

“…These advancements collectively contribute to the burgeoning field of quantum magnonics with promising avenues for scientific and technological progress. Therefore, this integration of diverse approaches is essential for unraveling the complexities of hybrid systems and harnessing their potential for technological innovation [2,152,155].…”