Improving mechanical cooling by using magnetic thermal noise in a cavity-magnomechanical system.

The cavity-magnomechanical system is a significant platform for studying quantum information. In this paper, a scheme to realize the ground-state cooling of the mechanical phonon mode in a cavity-magnomechanical system is proposed. In the general cooling method, the system is usually driven by a strong pumping field, and the Hamiltonian of the system needs to be linearized. Different from this cooling method, in a cavity-magnomechanical tripartite interaction system, we consider the magnetic thermal noise as an incoherent drive to facilitate cooling, where the thermal magnon number can enhance the effective coupling between the photon and phonon modes. The mechanical mode can be cooled to its ground state when the magnon thermal number is increased.