An international team of scientists were able to create the fastest mechanical rotation known to exist in history: nanoparticles spinning around each other at a billion times per second.
A joint project of scientists at Purdue, ETH Zürich, and a number of Beijing-based institutions, two teams independently created the intense spin with levitated optomechanical systems. These are systems which are extremely isolated from any outside environment and create a testing grounds of sorts for the basic fundamentals of physics.
The teams wanted to focus on the ways light’s energy can move nanoparticles, hoping to create quantum vacuum fluctuations in hopes of getting closer to understanding spacetime.
“In quantum mechanics, there are quantum vacuum fluctuations—virtual particles that appear and disappear. If a nanoparticle spins really fast, those kinds of virtual particles can perhaps provide friction,” says Tongcang Li, an assistant professor of physics and astronomy at Purdue University, to Gizmodo.
The team studied how began studying how they could use the particles levitated by light in a vacuum to create what’s known as a “torsion balance” to detect very slight changes in energy. With nanoscale silica dumbbells approximately 100 nanometers in diameter, the team began shining circularly polarized light, into the vacuum.
The light beams that make up circularly polarized light have electric fields which rotate as they move forward. When the polarized light hit the dumbbells, they began to spin. Not just spinning, but spinning at a billion times per second.
With no air in the vacuum to create any resistance, the particles are freed up to reach these remarkable speeds. The second team in Zürich also used silica nanoparticles, but they were not focused on studying spacetime. “We tried it out to see how fast we can go,” René Reimann, photonics professor at ETH Zürich, tells Gizmodo.
Quantum physics, studying the fundamental nature of the universe, can often yield astonishing results. Earlier this year, physicists discovered that photons are actually able to send messages to themselves.
Previously published by: Popular Mechanics USA