WASHINGTON, July 20 (Xinhua) -- American and Chinese researchers have created the fastest man-made rotor in the world, spinning at more than 60 billion revolutions per minute or over 100,000 times faster than a high-speed dental drill.
They described in a study published on Friday in the journal Physical Review Letters a tiny dumbbell from silica they synthesized.
They levitated the dumbbell in high vacuum using a laser. The laser can work in a straight line or in a circle: when it's linear, the dumbbell vibrates, and when it's circular, the dumbbell spins.
A spinning dumbbell can function as a rotor, and a vibrating dumbbell can function like an instrument for measuring tiny forces and torques, known as a torsion balance, according to the study.
"This study has many applications, including material science," said Li Tongcang, an assistant professor of physics and astronomy at Purdue University, who collaborated with researchers from Peking University, Tsinghua University and the Collaborative Innovation Center of Quantum Matter in Beijing.
Those rotating devices were previously used to discover things like the gravitational constant and density of Earth, but the researchers hoped that as the devices became more advanced, they would be able to study things like quantum mechanics and the properties of vacuum.
"People say that there is nothing in vacuum, but in physics, we know it's not really empty," Li said.
"There are a lot of virtual particles which may stay for a short time and then disappear. We want to figure out what's really going on there, and that's why we want to make the most sensitive torsion balance."
By observing this tiny dumbbell spin faster than anything before it, Li's team may also be able to learn things about vacuum friction and gravity.
Understanding these mechanisms is an essential goal for the modern generation of physics, Li said.
