Australian boffins have overcome one of quantum computing's big problems by building a gate comprised of two qubits in silicon, using techniques very similar to those used to manufacture whatever device you're using to read this story.

Building a quantum logic gate in silicon is a big deal because hitherto it's only been possible to build qubit-powered logic gates in exotic materials. While the world has considerable appetite for the step-change in computing power that quantum devices promise, the prospect of working with exotic materials is rather less welcome. Hence the significance of a new letter in Nature, titled “A two-qubit logic gate in silicon”, which explains how University of New South Wales boffins have been able to build cubits “using standard lithographic techniques.”

In a conventional computer, the presence or absence of an electron indicates a one or a zero. Quantum computers store information in the spin of an electron which, thanks to the weirdness of the world at quantum scale, can be in several states at once. A single electron in a quantum computer can therefore be a zero and a one at the same time, which creates the potential for parallel processing inside a chip and therefore for faster computation.

The UNSW boffins are bullish about the discovery outlined in the letter, proclaiming it represents “the final physical component needed to realise the promise of super-powerful silicon quantum computers.”

Note use of “physical component” as there's plenty of work to do before a quantum computer lands on your desk, complete with interfaces to peripherals, an operating system and software.

Killjoys? Us? Never: we're already excited at the prospect of one day acquiring a Quantum Pentium . ®