First functional quantum processor created, lasted slightly longer than your last Xbox 360

quantumcomputing posts

You know, at some point we're going to grow tired of just getting closer and demand that we arrive, but thankfully for a smattering of UK-based researchers, we're not yet to that point. Reportedly, brainiacs from Edinburgh and Manchester University have created a molecular machine that could be used to develop quantum computers for making "intricate calculations" far more quickly than current supercomputers. Essentially, these gurus relied on molecular scale technology instead of silicon chips; more specifically, they achieved the so-called breakthrough by "combining tiny magnets with molecular machines that can shuttle between two locations without the use of external force." Not surprisingly, there's still more work to be done, with Professor David Leigh of Edinburgh University noting that "the major challenges we face now are to bring many of these qubits together to build a device that could perform calculations, and to discover how to communicate between them." In other words, check back in 2012.
It looks like quantum computing could now be one step closer to some form of practicality, as a team of researchers from the University of Queensland have announced that they've created a light-based quantum circuit that's capable of performing basic calculations. According to ZDNET Australia, that was done by using a laser to send "entangled" photons through a linear optical circuit, which allowed them to create a circuit consisting of four "qubits," (or quantum bits, pictured at right), which in turn allowed them to calculate the prime roots of fifteen, three and five. Somewhat interestingly, the university's research is funded in part by none other than DARPA, which the researchers themselves admit may be due to the technology's potential for cracking otherwise uncrackable codes.
While we imagine most Wolverines are focusing their efforts on gathering up the requisite tailgating gear for the onset of fall, a team of researchers at the University of Michigan are busy finding ways to decipher encryption codes "within seconds." The crew has apparently discovered that by "using pulses of light to dramatically accelerate quantum computers," these systems could not only crack "highly encrypted codes" in moments versus years, but it could also "lead to tougher protection of [sensitive] information." Additionally, the findings rely on "quantum dots and readily available, relatively inexpensive optical telecommunications technology to drive quantum computers," which could lead to quicker implementation of quantum level applications. Hackers, meet your dream machine.
One of the many challenges facing quantum computing is finding a practical material from which to process the quantum information -- the material must not be so exotic such that it becomes too prohibitive and expensive to use for mass calculations. That's why a recently discovered hidden magnetic "quantum order" in ceramic has scientists in such a tizzy. By heating or doping the material with a variety of impurities, scientists from the London Center for Nanotechnology have found a way to propagate magnetic excitations over long chains of atoms in the otherwise magnetically disordered material. Armed then, with the ability to break the chains into independent sub-chains, each with it's own hidden order, scientists have taken the first step towards engineering spin-based quantum states from ceramics. Right, the quantum analogy to those good ol' 1 and 0 state changes used by today's not-so-super computers.
Researchers at the Max Planck Institute of Quantum Optics look to be doing their namesake proud, creating a single-photon server that could eventually lead to some significant advancements in quantum computing. The server was created by trapping a single Rubidium atom in a vacuum chamber and applying a laser pulse to it, which caused it to spit out one photon at a time. The key bit, it seems, is that the photons generated are of much higher quality than those derived using other methods, meaning that can essentially be made indistinguishable from one another -- a key requirement for quantum computing. With that considerable feat under their belt, the team, led by Professor Gerhard Rempe, have now set their sights on even less easily understandable experiments, including the case of the deterministic atom-photon and those always problematic atom-atom entanglements.
As you can imagine, here at Engadget, we love it when science fiction becomes more science and less fiction. With that in mind, we're pleased to pass along the news that Danish scientists at Copenhagen University have made a breakthrough in the wacky world of quantum teleportation by transporting quantum information over a distance of half a meter (1.6 feet). In order to achieve this, Dr. Eugene Polzik and his team shined a strong laser beam into a cloud of room-temperature cesium atoms that shared the same directional spin. As Scientific American reports: "The laser became entangled with the collective spin of the cloud, meaning that the quantum states of laser and gas shared the same amplitude but had opposite phases. The goal was to transfer, or teleport, the quantum state of a second light beam onto the cloud." (It should be noted that this process is more akin to duplication than actual teleportation, i.e. using this method on a human being would result in the formation of a doppelganger and not a magical Star Trek-like movement of matter). To achieve this goal, Polzik and other scientists added a second weaker laser pulse and split the two beams into separate branches in order to measure the difference between the quantum phases; through that measurement the scientists were then able to transfer the information of the spin state of the weak laser to the combination of the cesium atoms and the strong laser, without disturbing the quantum entanglement between the laser and the cesium. Umm, so the short of it is: one small step for a cesium atom, but one giant leap for quantum computing research and the advancement of teleportation theory.






