Choreographing dance of electrons

Reaching into the silicon crystal and choreographing the dance of 100 billion infinitesimal particles is an impressive achievement on its own, but it is also a stride toward developing the technology for powerful machines known as quantum computers.

"Standard computers have come to their limit and cannot do some of the things we want," said Tyryshkin, a research scholar in the Department of Electrical Engineering. "We are trying to find a different way of doing computing, using additional degrees of freedom involving quantum computing and things like spins."
Using the spins of subatomic particles such as electrons offers a path to developing a machine that would apply the reality-bending rules of quantum mechanics to arrive at new and powerful ways to approach difficult mathematical problems. But maintaining that control for long enough to build a working computer has proven incredibly difficult.

Until recently, the best attempts at such control lasted for only a fraction of a second. But researchers at Princeton led by Stephen Lyon, a professor of electrical engineering, have found a way to extend their control over the spins of billions of electrons for up to 10 seconds.

The researchers, part of an international team, reported their results online Dec. 4 in Nature Materials. The research at Princeton was supported by the National Science Foundation and the National Security Agency.
Lyon said the key to the new results lies in the use of a highly purified sample of silicon. The experiment uses a small silicon chip the size of a pencil lead made almost entirely of a particular isotope of silicon: silicon-28.