Quantum computing gets closer

The big brains at Yale make a quantum breakthrough.

Physics boffins at Yale University have made a quantum leap into the world of quantum computing, having managed to perform a couple of basic tasks on a solid-state chip that is essentially a two-qubit quantum processor.

Performing a search query may not seem like much, but to the team of physicists from Yale, the achievement is being celebrated as a major breakthrough on the road to quantum computing.

"Our processor can perform only a few very simple quantum tasks, which have been demonstrated before with single nuclei, atoms and photons. But this is the first time they've been possible in an all-electronic device that looks and feels much more like a regular microprocessor," said the team's leader, Robert Schoelkopf.

In an ordinary digital computer, a bit can either exist in the "1" or "0" position, corresponding to "on" or "off", respectively, whereas a qubit - subject to the laws of quantum mechanics - can exist as the superposition of both states simultaneously.

In the device, two simulated qubits, each made up of a billion aluminum atoms, are the building blocks of quantum computations. Basically, the billion aluminum atoms that make up each simulated qubit behave like a single particle that can occupy two different energy states at the same time. This opens up a whole range of possibilities for future computational performance.

Still, before you get too excited, the qubits generated so far have been extremely short lived. A decade ago, the first qubits that were created lasted only a nanosecond before they decayed, but the ones simulated in this chip last for an entire microsecond, a thousand times improvement.

"We're still far away from building a practical quantum computer, but this is a major step forward," said Schoelkopf.

More details about the solid-state quantum processor appear in the June 28th advanced online issue of the journal Nature.