dreamdancer 0 #1 November 16, 2009 the universal announcer says hello... QuoteThe world's first universal programmable quantum computer has been put through its paces. But the test program revealed significant hurdles that must be overcome before the device is ready for real work. Earlier in the year, a team at the National Institute of Standards and Technology in Boulder, Colorado, built a quantum computer capable of processing two quantum bits, or qubits. Qubits store more information than the simple "on" or "off" bits of conventional computing, which means that a quantum computer outperform conventional computers in tasks such as cryptanalysis. As in a classical computer, a series of logic gates processes the information – although here the gates are quantum logic, or qubit, gates. "For example, a simple single-qubit gate would change a 'one' to a 'zero' and vice versa," says David Hanneke, a member of the team. But unlike the physical logic gates of a classical computer, the quantum logic gates used in the team's device are each encoded into a laser pulse. The experimental device uses beryllium ions to store qubits in the way they spin while the laser-pulse quantum gates perform simple logic operations on the qubits. The trick to making a quantum logic gate is in designing a series of laser pulses that manipulate the beryllium ions in a way that processes information. Another laser then reads off the results of the calculations. "Once we had demonstrated we could successfully combine lots of components in this way, we ask: what can you do with that?" says Hanneke. They found their answer in quantum computational theory. "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," says Hanneke. Although one and two-qubit gates have already been built and used to perform specific algorithms, no one had yet built a device capable of all possible quantum routines. Until now. http://www.newscientist.com/article/dn18154-first-universal-programmable-quantum-computer-unveiled.htmlstay away from moving propellers - they bite blue skies from thai sky adventures good solid response-provoking keyboarding Quote Share this post Link to post Share on other sites
