Cryogenic magnomechanics for thermometry applications

Cavity magnomechanics combines strong coupling between magnons in a dielectric material and microwave cavity photons with long-lived mechanical resonances. Forming a triple resonance condition, this hybrid quantum system promises many advantages in quantum technologies, yet has never been studied at the cryogenic temperatures required to reveal such quantum properties. We report the observation of magnomechanics at cryogenic temperatures down to 9 K. The experiment was conducted using a yttrium iron garnet sphere inside a microwave cavity, where we measured both the thermomechanical motion and the temperature-dependence of the magnon linewidth.