Quantum Algorithms
Thursday, May 13, 2004
Entanglement beats the diffraction limit
PhysicsWeb - Entanglement beats the diffraction limit: "Physicists have succeeded in 'entangling' more than two photons for the first time. A Canadian team has entangled three photons while an Austrian team have created a four-photon entangled state. The wavelengths of the entangled states are three and four times shorter than the original wavelengths of the photons. By overcoming the so-called diffraction limit, entangled photons could prove useful in a range of applications ranging from lithography to microscopy."
Tuesday, May 11, 2004
Comments Enabled
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Quantum Pontiff: Thumbs up for Ion Trap QC's
In The Quantum Pontiff: Focus, People! Dave Bacon has some observations from a QC workshop he attended, and he thinks Ion Traps are way ahead of any other implementation: "Ion traps rock. If [I] were a starting graduate student who wanted to do quantum computing and do some really rocking quantum computing experiments during my graduate career I would make a dash straight towards an ion trap quantum computing group. The era of NMR is over and a new era of Ion trap quantum computing has begun! "
Thursday, May 06, 2004
Physics Researchers Find Striking Quantum Spin Behavior
Physics Researchers Find Striking Quantum Spin Behavior: "Describing spinning bosons [...] requires a tensor polarization which has one more dimension than a vector polarization [...]. A speculative, but perhaps possible, application of this research comes from the spinning bosons’ extra dimension. This might make the still-speculative but promising quantum computers more effective, because much more information could be stored in the extra dimension"
QCs in Japan
The Japan Times Online, Japan leading quest for first quantum computer: "NTT Basic Research Laboratories in Atsugi, Kanagawa Prefecture, whose quantum computer research is considered the most advanced in the world, has confirmed the superposition of quantum states -- the coexistence of 0s and 1s in a single quantum bit." The article mentions that the Japanese government does not have enough money to fund quantum computer research, so it will have to be led by corporations, in Japan at least.
Saturday, May 01, 2004
Advance in Quantum Electronics
From ABC Australia, News in Science - Faster electronics ahead, says new theory: "A new theory on how electrons behave in ultra small devices threatens to overturn one of the tenets of quantum electronics."
Optical Quantum Memory Designed
From Technology Review, Optical Quantum Memory Designed: "The researchers' quantum transponder design calls for encoding pairs of quantum bits in sets of four photons in such a way that the two qubits can be read even if one of the four photons is lost. Qubits would be sent into a fiber loop and a simple quantum computer would correct for errors caused by photons being absorbed by the fiber. The design includes a device to generate single photons to replace lost photons."
Entangled Quantum Dots
From AScribe.org, Quantum Computers Are a Quantum Leap Closer: "The team used eight tiny converging wires, or 'gates,' to deposit the electrons in the dots one by one and then electronically fine-tune the dots' properties so they would become entangled. With these gates, the team was able to slowly tune the interacting dots so they are able to exist in a mixed, down-up and up-down configuration simultaneously."
Quantum Money Transaction
From the free section of Nature: Business goes quantum: Money changes hands in key bank transaction: "One of the most secure methods of quantum cryptography has been used commercially - for a single transaction, at least. On 21 April, Austrian scientists used the technique to transfer a 3,000 (US$3,500) donation to their lab."