Dr Yoshihiki Arita, Dr Michael Mazilu and Professor Kishan Dholakia of the School of Physics and Astronomy at the University of St Andrews were able to levitate and spin a microscopic sphere, purely using laser light in a vacuum, briefly up to 600 million RPM before it broke apart.
This speed is half a million times faster than the spin speed of a domestic washing machine and more than a thousand times faster than a dental drill.
Although there is much international research exploring what happens at the boundary between classical physics and quantum physics, most of this experimental work uses atoms or molecules. The St Andrews team aimed to understand what happened for larger objects containing a million million atoms or more.
To do this they manufactured a microscopic sphere of calcium carbonate only 4 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 - rather like levitating a beach ball with a jet of water.
They 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 (friction) due to any gas environment, allowing the team to achieve the very high rotation rates.
In addition to the rotation, the team 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
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