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Paint-on Laser Brings Optical Computing Closer
holy_calamity writes "New Scientist has a story about a laser made by painting a solution of semiconductor crystals onto glass. It could be used to break the interconnect barrier by having optical interconnects, the interconnect barrier threatens Moore's law unless a faster way of connecting chips is found."
Is there any chance this paint is waterproof.
Sincerely,
Dr Evil.
liqbase
The intention of quantum computing is not to replace, but rather to complement classical (i.e. digital) computing. Quantum computing can dramatically speed up certain tasks, such as cryptography and searching. Even though they cannot yet be implemented, a number of important quantum algorithms have already been discovered. Most - but not all - quantum algorithms return probabilistic answers, rather than clear-cut answers as most classical algorithms do.
Shor's algorithm for factoring numbers could be used to rapidly crack RSA encryption. http://en.wikipedia.org/wiki/Shor's_algorithm
Grover's algorithm can be used to search an unsorted database in O(n?2) time. http://en.wikipedia.org/wiki/Grover's_algorithm
The article and summary seem to be a bit misleading and vauge about how the speed increase arrises. The great benefit of optical computing is that it allows the signals to get much much closer together than electronic circuits, and as such allow more compact circuits, which as we know generally means faster. Interestingly, electronic signals in wires and optical signals in fibers have roughly identical upper speed limits (light in free-space optical computers is faster, but also almost impossible to do anything useful with), so its the density which is the major factor.
Electrons are charged, so as you squeeze transistors closer together, the wires get thinner and closer together, and you get cross-talk and interference between them. Photons however hardly interact at all, so you can have many beams in the same space, and theres very little heat to be dissipated. Multiplw frequencies can also be used, resulting in massivly parallel computing (another GoodThing).
There are downsides with optical computing still, photons cannot be stopped and stored (easily), meaning any kind of useful computer in the near term is likely to be some sort of electro-optical hybrid, with photons carrying signals and electrons storing them