Scientists 'Listen' to an Atom?

In a novel study, scientists have captured the sound of a single atom, showing that they can effectively communicate with an atom via sound, not just light.

"We have opened a new door into the quantum world by talking and listening to atoms," lead researcher Per Delsing said in a statement. "Our long term goal is to harness quantum physics so that we can benefit from its laws, for example in extremely fast computers."

The findings were published in the journal Science.

Scientists have long understood the relationship between atoms and light via the field of quantum physics, but sound is a horse of a different color. A team at Chalmers University of Technology in Göteborg, Sweden is the first to use sound waves to communicate with an atom, albeit and artificial one.

An artificial atom, just like a regular one, can be charged up with energy which it subsequently emits in the form of a particle. This is usually a particle of light, but in this case the researchers designed the atom to both emit and absorb energy in the form of sound - more specifically, as surface acoustic waves (SAWs) which appear as ripples on the surface of a solid.

"According to the theory, the sound from the atom is divided into quantum particles," explained co-author Martin Gustafsson, a post-doctoral researcher at Columbia University. "Such a particle is the weakest sound that can be detected."

That sound was a "D-note" about 20 octaves above the highest note on the piano, which is a pitch much higher than the human ear can detect.

The Chalmers team says that their research opens up the door to new developments in quantum computing. Sound has a short wavelength and travels 100,000 times slower than light, which means it's much easier to control.

"Whether it has implications for quantum computing may be too early to tell, but it expands the toolbox for technologies to work with," Steve Rolston, co-director of the University of Maryland's Joint Quantum Institute, who was not involved in the study, told Discovery News.