Quantum computing researchers at the University of Oxford have developed a logic gate with a precision of 99.9%. That's not only a new record, it also hits the theoretical benchmark necessary to build a real quantum computer.
Logic gates are one of the crucial components inside every computer, and - for that matter - pretty much any digital system. They change inputs into outputs based on a certain logic. An AND gate, for example, will only switch on its output if both of its two inputs are activated.
The team built a quantum version by placing two atoms in a state of "quantum entanglement" - an action on one affects the other. Researchers have done this before, but this time the fidelity of the link was substantially greater than any previous attempt.
David Lucas, a co-author on the paper describing the discovery in Physical Review Letters, explains: 'A quantum logic gate is an operation which can take two independent atoms and put them into this special entangled state.
The precision of the gate is a measure of how well this works. In our case, 99.9% precision means that, on average, 999 times out of 1,000 we will have generated the entangled state correctly, and one time out of 1,000 something went wrong.
He added: "To put this in context, quantum theory says that - as far as anyone has found so far - you simply can't build a quantum computer at all if the precision drops below about 99%.
"At the 99.9% level you can build a quantum computer in theory, but in practice it could very difficult and thus enormously expensive. If, in the future, a precision of 99.99% can be attained, the prospects look a lot more favourable."
Quantum computing is one of the major challenges facing physicists right now. While the technology remains in its infancy, it holds great promise - far above traditional computing technologies.
Chris Ballance, the lead author of the paper, said: "It is not merely a different technology for computing in the same way our everyday computers work; it is at a very fundamental level a different way of processing information.
"It turns out that this quantum-mechanical way of manipulating information gives quantum computers the ability to solve certain problems far more efficiently than any conceivable conventional computer."