World`s fastest spinning man-made object created
Scientists, including one of Indian-origin, claim to have developed the world`s fastest spinning man-made object.
London: Scientists, including one of Indian-origin, claim to have developed the world`s fastest spinning man-made object.
Researchers were able to levitate and spin a microscopic sphere at speeds of up to 600 million revolutions per minute - a speed that is half a million times faster than a domestic washing machine and more than a thousand times faster than a dental drill.
For the experiment, the University of St Andrews team manufactured a microscopic sphere of calcium carbonate only four millionths of a metre in diameter.
The team then used the miniscule forces of laser light to hold the sphere with the radiation pressure of light - like levitating a beach ball with a jet of water.
The research exploited the property of polarisation of the laser light that changed as the light passed through the levitating sphere, exerting a small twist or torque.
Placing the sphere in vacuum largely removed the drag due to any gas environment, allowing the team to achieve the very high rotation rates.
The team also observed a "compression" of the excursions or "wobble" of the particle in all three dimensions, which can be understood as a "cooling" of the motion.
Essentially the particle behaved like the world`s smallest gyroscope, stabilising its motion around the axis of rotation, researchers said.
"This is an exciting, thought-provoking experiment that pushes the boundary of our understanding of rotating bodies. I am intrigued with the prospect of extending this to multiple trapped particles and rotating systems," said Dr Yoshihiko Arita of the university`s School of Physics and Astronomy.
"We may even be able to shed light on the area of quantum friction - that is does quantum mechanics put the brakes on the motion or spinning particle even though we are in a near perfect vacuum with no other apparent sources of friction," Arita said.
Another member of the team, Professor Kishan Dholakia, said he believed the team had "performed a real breakthrough piece of work" that would resonate with the international community.
"In addition to the exciting fundamental physics aspects, this experiment will allow us to probe the nature of friction in very small systems, which has relevance to the next generation of microscopic devices. And it`s always good to hold a `world record` - even if for only a while," he said.
The research was published in journal Nature Communications.