Sensing weak force using a diamagnetic levitated micromechanical oscillator

Levitated mechanical oscillator in high vacuum is supposed to be an ideal system for sensing weak force, and diamagnetic levitated oscillator is recently developed with typical working frequency in 1Hz to 100Hz range, especially, diamagnetic levitation is fully passive and suitable for cryogenic condition operation, we will introduce the realization of cryogenic diamagnetic levitation where ultra-low mechanical dissipation is observed, we also introduce a lens-free detection scheme that can applied to detecting oscillator of sub-millimeter size which can be used for acceleration sensing, we finally give examples of application of diamagnetic levitation to the problem of wave function collapse and dark matter particle.