# Quantum Acoustomechanics with a Micromagnet

## TL;DR

This paper proposes a method to strongly couple a micromagnet's center-of-mass motion with acoustic phononic modes using magnetic fields, enabling quantum control and manipulation of mechanical vibrations.

## Contribution

It introduces a theoretical scheme for quantum coupling between micromagnet motion and acoustic modes via magnetic field tuning, applicable to levitated and clamped micromagnets.

## Key findings

- Coupling can be tuned to ground state cooling or strong quantum regime.
- Feasible parameters for experimental realization.
- Applicable to both levitated and clamped micromagnets.

## Abstract

We theoretically show how to strongly couple the center-of-mass motion of a micromagnet in a harmonic potential to one of its acoustic phononic modes. The coupling is induced by a combination of an oscillating magnetic field gradient and a static homogeneous magnetic field. The former parametrically couples the center-of-mass motion to a magnonic mode while the latter tunes the magnonic mode in resonance with a given acoustic phononic mode. The magnetic fields can be adjusted to either cool the center-of-mass motion to the ground state, or to enter into the strong quantum coupling regime. The center-of-mass can thus be used to probe and manipulate an acoustic mode, thereby opening new possibilities for out-of-equilibrium quantum nanophysics. Our results hold for experimentally feasible parameters and apply to levitated micromagnets as well as micromagnets deposited on a clamped nanomechanical oscillator.