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Researchers wed quantum processor with quantum memory, quaziness ensues
Quantum computing has a long way to go before becoming truly mainstream, but that certainly hasn't stopped us from indulging in dreams of a qubit-based existence. The latest bit of fantasy fodder comes from the University of California, Santa Barbara, where researchers have become the first to combine a quantum processor with memory mechanisms on a single chip. To do this, Matteo Mariantoni and his team of scientists connected two qubits with a quantum bus and linked each of them to a memory element, capable of storing their current values in the same way that RAM stores data on conventional computers. These qubit-memory links also contained arrays of resonators -- jagged, yet easily controlled circuits that can store values for shorter periods of time. The qubits, meanwhile, were constructed using superconducting circuits, allowing the UCSB team to nestle their qubits even closer together, in accordance with the von Neumann architecture that governs most commercial computers. Once everything was in place, the researchers used their system to run complex algorithms and operations that could be eventually used to decode data encryption. The next step, of course, is to scale up the design, though Mariantoni says that shouldn't be too much of a problem, thanks to his system's resonators -- which, according to him, "represent the future of quantum computing with integrated circuits."
D-Wave One claims mantle of first commercial quantum computer
Whether or not D-Wave has actually built a quantum computer is still a matter of debate (though, a study authored by the company and published in Nature claims to prove its success) but, whatever it is these crafty Canadians have created, you can order one now and start crunching qubits with abandon. The D-Wave One is the first commercially available quantum computer and, while its 128-qubit processor can only handle very specific tasks and is easily outperformed by traditional CPUs, it could represent a revolution in the field of supercomputing. As D-Wave scales up to thousands or tens-of-thousands of qubits, complex number theory problems and advanced cryptographic systems could crumble before the mighty power of quantum annealing... or at least give us faster Google searches. Just out of curiosity, we contacted D-Wave to see how much we'd have to cough up for a quantum desktop of our own, but we've yet to hear back. Update: Joseph passed along an e-mail from the company with a little more information, including a price: $10,000,000. Yep, ten large, and we're not sure that includes the liquid helium required to keep it cooled.
Researchers show off scalable architecture for quantum computing, expand our minds
Okay, so we might be chasing the flying unicorn of modern technology here -- and, no, we're not talking about the white iPhone 4 -- but as you've probably noticed, our hunger for a quantum computer is basically insatiable. Lucky for us, some folks who actually know something about producing qubits are similarly persistent -- a team of researchers recently presented a scalable quantum chip at a meeting of the American Physical Society in good old Texas. The 6 x 6-cm processor sports four qubits, the basic units of quantum computing, and its creators say it has the potential to be scaled up to support 10 of the things within the year. So what does that mean for our quest for the ultimate super computer? Well, it means we're closer than we used to be... and the dream lives on.
Northwestern University researchers route photon qubit, make quantum internet possible
Big brains across the globe continue to unlock the secrets of the qubit and harness it for myriad uses -- quantum hard drives, quantum computers, and even quantum refrigerators. The internet may be next in line to get quantum-ized now that researchers from Northwestern University found a way to route a photon qubit through an optical cable without losing any of its physical characteristics. A newly developed optical switch does the deed, which allows fiber-optic cables to share multiple users' quantum info at once -- making superfast all-optical quantum communication networks possible -- and gets us closer to having our tweets and status updates whizzing to and fro at the speed of light. [Thanks, Jonathan C]
Scientists create 10 billion qubits in silicon, get us closer than ever to quantum computing
We are totally ready for a quantum computer. Browse the dusty Engadget archives and you'll find many posts about the things, each charting another step along the way to our supposed quantum future. Here's another step, one that we think is a pretty big one. An international team of scientists has managed to generate 10 billion quantum entangled bits, the basic building block of a quantum computer, and embed them all in silicon which is, of course, the basic building block of a boring computer. It sounds like there's still some work to be done to enable the team to actually modify and read the states of those qubits, and probably a decade's worth of thumb-twiddling before they let any of us try to run Crysis on it, but yet another step has been made. [Image credit: Smite-Meister]
Dark excitons could light up your quantum computer, life
Yeah, we're still hanging around playing Q*bert and waiting on folks to get those qubits a spinning. Meanwhile, researchers have found a new path to follow on the way to quantum enlightenment. A new, darker path, which entails the use of so-called dark excitons as quantum bits. While doubling as a great name for future robo-gigolos, a dark exciton is an electron-hole pair with parallel spins. The parallel spin, which makes this quasiparticle "dark," also enables it to be long-lasting and, critically, to be excited with an electrical charge to set its state, a state that can then be read by looking for an emitted photon. Fascinating? Absolutely. Coming to a desktop near you? Not likely -- not unless your desktop is kept at a temperature of 4.2K, anyway. [Image credit: Smite-Meister]
Researchers develop means to reliably read an electron's spin, take us one step closer to the quantum zone
Another day, another step bringing us closer to the next big revolution in the world of computing: replacing your transistory bits with qubits. Researchers at Australia's Universities of New South Wales and of Melbourne, along with Finland's Aalto University, have achieved the impossibly tiny goal of reliably reading the spin of a single electron. That may not sound like much, but let's just see you do it quickly without affecting said spin. This particular implementation relies on single atoms of phosphorus embedded in silicon. Yes, silicon, meaning this type of qubit is rather more conventional than others we've read about. Of course, proper quantum computers depend on reading and writing the spin of individual electrons, so as of now we effectively have quantum ROM. When will that be quantum RAM? They're still working on that bit.
String theory finds an elegant use for itself with qubit entanglement and black holes
Sure, trying to wrap your head around string theory -- a study in particle physics that's trying to rectify the perceived contradictions between general relativity and quantum mechanics -- can cause more cognitive pain than a colliding god particle. That hasn't stopped anyone from trying to validate its corollaries, and in the interim, researchers like Michael Duff of the Imperial College London. Mr. Duff realized a few years ago there existed some strong relations between formulas pertaining to both black holes (relativity) and four entagled qubits (quantum mechanics). So, in his words, "In a way, there's bad news and good news in our paper. The bad news is, we're not describing the theory of everything. The good news is, we're making a very exact statement which is either right or wrong. There's no in between." We're sure some science cliques are already gearing up to get their troll on. Hit up the PDF below if you want to read it yourself.
Quantum refrigerator could cool your quantum computer, allow for quantum overclocking
The quantum computer is still ranking pretty high up there on the vaporware charts, somewhere between Duke Nukem Forever and a Steorn in-home power generator. Eventually we'll get there, and theoretical physicists at the University of Bristol are helping with a quantum cooling system. It is effectively a means for two qubits to cool a third, with the outer two cooled by lasers and absorbing energy from the third, which is heated to its excited state. Unsurprisingly this is all rather theoretical at this point, but the team does plan to actually build such a quantum refrigerator in the not too distant future. Then, we figure, they'll host the first quantum kegger.
Google working with D-Wave on what may or may not be quantum computing
When we first mentioned D-Wave way back in early 2007 we immediately compared it to Steorn -- less than optimal beginnings. The company was promising quantum computing for the masses and, while it did demonstrate a machine that exhibited qubit-like behavior, the company never really silenced critics who believed the underpinnings of the machine were rather more binary in nature. Those disbelievers are surely shutting up now, with word hitting the street that Google has signed on, building new image search algorithms that run on D-Wave's C4 Chimera chip. The first task was to learn to spot automobiles in pictures, something that the quantum machine apparently learned to do simply by looking at other pictures of cars. It all sounds rather neural-networkish to us, but don't let our fuzzy logic cloud your excitement over the prospect of honest to gosh commercial quantum computing.
NEC wires up a quantum circuit
The quantum computing train keeps rumblin' on as researchers at NEC have managed to develop a "tunable coupler," enabling them to wire up what they're saying is the world's first quantum "circuit." The coupler connects two qubits, quantum bits that can be set to either 1, 0, or "both" (that's where the power of quantum computing lies), but unlike previous coupling attempts, does not significantly shorten the useable lifetime of the qubit. NEC says the microwave-controlled circuit is theoretically capable of scaling up to a system comprising enough qubits to outperform most modern supercomputers, but further development in preserving qubit lifetimes is necessary to make the tech viable. Better hurry up, guys -- D-Wave is already solving Sudoku.
World's first "commercial" quantum computer solves Sudoku
As expected, Canada's D-Wave Systems has announced "the world's first commercially viable quantum computer," and they seem to be pretty stoked about it. The achievement is notable, since they've managed to build a whole 16 qubit computer that actually does some simple computations, even if it's far less powerful than even the most basic of home computers. Qubits are quantum bits that can be in an "on," "off" or "both" state due to fuzzy physics at the atomic level, and up until now the best anyone had done was get three qubits together for computing. This 16-bit version can solve Sudoku, create a complicated seating plan and search for molecular structures, but quantum computers will need to be in the range of thousands of qubits to be able to solve puzzles -- such as encryption -- that current computers cannot. D-Wave is planning to have a 1,000 qubit version ready by the end of next year, but scientists in the field are skeptical. The adiabatic method used by D-Wave, which cools electronic circuits into a superconducting state, with the resulting qubits being slowly varied in a magnetic field, might not be able to keep its speed when on that large of a scale. "It probably won't work but it's not quixotic," says Seth Lloyd of MIT. "If it works then they can solve really hard problems and they'll be very much in demand," he says. But it's a long shot: "It's certainly not the kind of company I'd invest my money in." To raise awareness, D-Wave will be opening the computer up to computational problems over the internet after the results of the project are peer-reviewed. More pics after the break.[Via Digg]
