Levitated Superfluid Helium Drops as Unclamped Optomechanical Cavities

Optomechanics enables extremely precise measurements by coupling optical resonators to mechanical motion. We are developing a levitated optomechanical platform based on millimeter-scale drops of superfluid helium diamagnetically levitated in a strong magnetic field inside an ultrahigh-vacuum, cryogenic environment, which provides strong isolation from external mechanical and thermal noise. The drop's surface can support optical whispering gallery modes, while capillary surface oscillations provide a mechanical degree of freedom. I will discuss our progress on building and characterizing this system, including upgrades for improved optical access and imaging, and our plans for tunable control of the system.