Researchers in Singapore have accelerated a tiny magnetic rotor to a record-breaking 138 million revolutions per minute inside a superconductor trap.
The spherical magnet, constructed from neodymium, iron, and boron, measures about 30 micrometres wide, roughly matching the width of a fine human hair, according to New Scientist. Tao Wang at the Agency for Science Technology and Research in Singapore and colleagues placed the rotor inside a cylindrical lead container housed within a vacuum chamber.
Liquid helium chilled the setup to roughly -269°C (-452°F), allowing the lead to act as a superconductor that repelled magnetic fields through the Meissner effect. This magnetic repulsion caused the rotor to levitate without particle friction, while a magnetic coil set the object spinning.
The levitated rotor maintained exceptional stability during operation. According to measurements cited by New Scientist, it would take 17 days for the spinning speed to decrease by 50 per cent.
In terms of how many turns it makes before slowing down significantly, this is in the same league as the Earth’s spinning,
Tao Wang, Agency for Science Technology and Research
Wang also noted the unprecedented nature of the device, stating This, so far, is the fastest magnetically levitated rotor.
While laser-levitated nano-spheres hold the overall record for human-made rotating objects, those items remain invisible to the naked eye. Because the new magnetic rotor operates cold and experiences virtually no friction, researchers have successfully tested it as a vacuum gauge at very low temperatures.
Benjamin Stickler at Ulm University in Germany noted that the system could precisely sense and measure magnetic fields. Andrea Vinante at the National Research Council in Italy added that the platform might assist in searching for dark matter particles or sensing gravitational waves at unexplored frequencies.
