Quantum computation successful in silicon for the first time

New Scientist : Quantum computing makes use of qubits, which can take the values 0, 1, or combinations thereof. However, all the qubits that have ever been used in calculations have been supercooled superconductors. Now, Andrew Dzurak of the University of New South Wales in Sydney, Australia, and his colleagues have created qubits from a pair of silicon transistors. Their arrangement is essentially a basic logic gate: The device examines the spin of one electron and then either flips the spin of a second electron or leaves it alone based on the direction of spin of the first. By combining those gates, the logic system can perform complex calculations. Dzurak and his team say they have a design for a chip containing millions of the qubits. However, the silicon-based qubits are still outperformed by their superconductor counterparts.