Ground-state cooling of a magnomechanical resonator induced by magnetic damping

Abstract

Quantum manipulation of mechanical resonators has been widely applied in fundamental physics and quantum information processing. Among them, cooling a mechanical system to its quantum ground state is regarded as a key step. In this work, we propose a scheme that can realize ground-state cooling of the resonator in a cavity magnomechanical system. The system consists of a microwave cavity and a small ferromagnetic sphere, in which phonon–magnon coupling and cavity photon–magnon coupling can be achieved via magnetostrictive interaction and magnetic dipole interaction, respectively. Within experimentally feasible parameters, we demonstrate that the extra magnetic damping can be utilized to achieve ground-state cooling of the magnomechanical resonator via an effective dark-mode interaction. The magnomechanical cooling mainly comes from the magnon–phonon interaction terms. We further illustrate that optimal cooling can be obtained by adjusting the external magnetic field.