Tiny levitated magnets are able to avoid contact friction, making them useful for detecting extremely weak forces and magnetic fields and acting as ultralow-noise quantum sensors and precision measurement tools. Combining levitation with extreme cold further reduces unwanted motion that can make faint signals hard to detect.
Spinning magnets have even better magnetic sensitivity, but levitated micromagnet experiments have so far mainly studied back-and-forth motion, rather than continuous spinning. And experiments with spinning magnets have thus far stayed in the macroscopic realm, with magnets around half a millimeter in diameter.
But now, researchers report the first experiments with a levitated spinning micromagnet, and this tiny magnet is much faster than the macroscopic version. The new study, published in Science Advances, describes how this microscopic rotor achieved record-breaking rotational speed and how it’s already helping in the search for dark matter particles.









