Scientists play ping-pong with single electron using paddles made of sound

Technically, any sound moves electrons, since electrons are part of the atoms that move in pressure waves. But now scientists are using sonic waves to move an electron down a wire perfectly - with no loss of information. Then they played ping-pong with it. Typical.

Wires are supposed to channel and control electricity. They give the impression of speed and efficiency when they power our appliances or light our streets or zap us until our arms are numb because we accidentally touched the place on the power cord that one of our pets chewed through. But that remarkable electric speed and efficiency is relative. Electrons moving through a wire are like water drops moving through a river. They're fine if what you need is bulk flow to power a dam, but the path of a single drop is circuitous, and controlling it is impossible.

Efficiently channeling an electron was similarly impossible, until recently. Electrons moving down a wire would slalom one way and another. As computers came on the scene, and then shrank down to palm-top size, individual electrons needed to get from one place to another efficiently, and one at a time. To do this, scientists have to carve out a path for each electron and make sure it hops quickly and efficiently along. In a project to be pulished in Nature, they do that just.

First scientists need a piece of gallium arsenide. Inside this piece of arsenide they need to carve out little wells, each four microns apart. These wells hold the electrons, but the scientists need some power source gentle enough to scoot the electron from one well to the next without jumbling it up. It turns out that that power comes from sound. Delicate sound waves, billionths of a second long, compress the wire and make the electron to make it move along the wire to the next well without any interference.

Scientists have managed to play 'ping-pong' with an electron, sending it back and forth from well to well sixty times. Control over single electrons may be a way to make quantum computing a reality.

Not sure how it would work with mp3 players, though.

Via Cambridge University.