Researchers from the American facility have just created the fastest rotating object in the world. This one carries out about … 300 billion revolutions per minute, which is about 500,000 times as much as a dental drill. This object is an incredibly small silica nanoparticle that looks like two spheres joined together when viewed through an electron microscope.
This is what the world's fastest rotating object looks like under an electron microscope | Source: Purdue University / Jaehoon Bang
To put the molecule into such a fast vortex, scientists used … the power of light. First, they suspended the object in a state of levitation in a vacuum with a laser, and then used another laser to accelerate it, we read in a study published in the journal Nature Nanotechnology. This is possible because the light particles – known as photons – act with a small but measurable force on every object they come into contact with. This force is known as the pressure of light radiation and is millions of times weaker than gravity.
"In 1600, Jan Kepler noticed that comet tails were always directed away from the sun because of radiation pressure", said Tongcang Li, professor of physics and astronomy and professor of electrical and computer engineering at Purdue. "We use the same phenomenon, but with concentrated lasers – to levitate and rotate nanoparticles."
What is extremely interesting all of the above is not exclusively "art for art". Scientists say the nanoparticle also serves as the most sensitive torque detector known. Torque is a measure of the force that causes an object to rotate around an axis. The device is 600-700 times more sensitive than any other device created so far that can measure torque.