The machine with a heart of gold

First programmable quantum computer is revealed.

The world's first universal programmable quantum computer has been unveiled in Colarado by the National Institute of Standards and Technology.

According to a report in New Scientist, the machine still needs to overcome some ‘significant hurdles', but it is capable of processing two quantum bits or qubits. These can store a lot more data than your common or garden "on" or "off" bits of conventional computing.

Although one and two-qubit gates have been built and used to perform specific algorithms before, no one has built a device capable of all quantum routines 'til now.

The team used quantum computational theory to push the computer to the next level. "One of the more interesting results to come out of the early years of quantum information was that you can do any quantum operation on any number of qubits using only single and two-qubit logic gates," said David Hanneke, who led the team.

The quantum logic gate was made by manipulating beryllium ions with a series of laser pulses in a way that processes information. Then another laser reads off the results of the calculations.

The device even has a heart of gold. Well, a gold-patterned aluminium wafer with an electromagnetic trap some 200 micrometres across. In the trap the team placed four ions. Two made of beryllium and two of magnesium. The latter stop unwanted vibrations from the ion chain and keep the device stable.

There are an infinite number of possible two-qubit operations. When demonstrating the universality of the processor, the team chose a random selection of 160, running each program 900 times.

"But it did so with an accuracy of only 79 per cent. Each gate is more than 90 per cent accurate but when you stack them together the total figure falls to 79 per cent or so for a given operation," Hanekke said.

The laser stability is one of the biggest factors for error, he revealed.