As early as July 2018, researchers at Purdue University created the world’s fastest-rotating object, which rotates at a rate of 60 billion revolutions per minute. Now the same research team has broken its own record using the same technique, creating a new nanoscale rotor that rotates five times faster.
As in earlier versions, the rotating object spun is a dumbbell-shaped silica nanoparticle suspended in a vacuum. When it started spinning, the new model reached an ultra-fast rate of 300 billion revolutions per minute. For comparison, the dentist’s drill is known to spin up to 500,000 revolutions per minute, while the fastest pulsar (the fastest natural object to rotate it) rotates at 43,000 revolutions per minute.
Setting this record involves irradiating two lasers on nanoparticles. One holds it in place, while the other rotates it. When the photons that make up light hit an object, they exert a small force on the object, i.e. radiation pressure. Typically, this force is too weak to produce any obvious effect, but in a vacuum, friction recording speed is almost impossible. This also applies to the concept of light sails, which could one day propel spacecraft at high speed.
“In the 17th century, Johannes Kepler observed that comets’ tails always carry the sun because of radiation pressure,” said study author Li Tsing-tibet. We use the same thing, but use a concentrated laser to suspend and rotate nanoparticles. “
In addition to breaking world records, the device could also be used to measure quantum effects such as vacuum friction and nanoscale magnetism, the researchers said.
The study was published in the journal Nature Nanotechnology.