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Majorana Fermion May Have Been Spotted At TU Delft
vikingpower writes "A research group at Technical University Delft around prof. Kouwenhoven has probably not only spotted pairs of so-called Majorana Fermions for the first time (these had been predicted to exist by the Italian physicist Ettore Majorana), but also demonstrated that, by generating them at the end of an Indium-Arsenide microwire, quantum computing with them may have come one more step closer to reality. The excitement around Prof. Kouwenhoven at the American Physical Society annual congress in Boston, after he completed his presentation, was considerable.A nice illustration is provided by this newspaper article (in Dutch)."
It didn't say Marijuana
The picture and article differ in the wire composition, so which is it?
indium-antimonide or indium-arsenide?
Any sufficiently advanced technology is indistinguishable from magic. But it is not magic.
Moral of the story?
There is no such thing as magic.
Any cool ass magic will be indistinguishable from sufficiently advanced technology.
Why is it so hard to only have politicians for a few years, then have them go away?
Note we're talking about condensed matter physics here, so this isn't the discovery of a fundamental particle that is a Majorana fermion, just a composite particle (similar to a Cooper pair) that appears to behave like a Majorana fermion. I'm sure this is an exciting discovery, but I tend to get more excited about fundamental particle discoveries.
BTW, maybe someone can enlighten me further, but since neutrinos have mass wouldn't they probably have to be Majorana fermion? You could catch up to a neutrino and make it appear as right-handed in some reference frame which would presumably make it's anti-matter right-handed counterpart? Neutrinoless double-beta decay is what would confirm that, right?
This is not a discovery of real elementary particle, instead it is a quasiparticle. It behaves (in its quantum properties) like Majorana Fermions, much in the same way a "hole" in a semiconductor behaves like a positively charged particle.
It takes many small steps to complete a long journey. You seeing many similar announcements because progress is being made...
I may or may not have butchered this, but I think its better than googles. All edits from original google translation are mine, as are any omissions.
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Since 1937, physicists in Delft have sought to observe evidence of Majorana fermions, a fundamental particle whose properties may soon be used in quantum supercomputing.
Recently, Delft physicists have claimed to be the first to create this exotic new elementary particle, showing in addition how it can play a key role in the supercomputer of the future. They made their discovery not in a giant particle accelerator, but at the intersection of superconducting nanowires on a chip.
Prof. Leo Kouwenhoven, who made the discovery, announced the results at the annual meeting of the American Physical Society (APS). The news caused a wave of excitement among the thousands of present physicists. A reporter of the weekly Nature likened the situation to a busy train station during rush hour.
"Have we seen Majorana fermions? I'd say a cautious 'yes'", stated Kouwenhoven at the end of his presentation in Boston. Other physicists said that the Delft measurements cannot be explained other than by the presence of a Majorana-like particle.
The results have been published in the journal "Physical Review Letters". The so-called Majorana-fermion is one of the strangest elementary particles that physicists know, at least on paper. The possible existence was predicted in 1937 by the Italian physicist Ettore Majorana (1906-1938). Since then, physicists have looked everywhere for natural Majorana particles, but without success. Several years ago, attention was shifted to the observable effects in some solids which Majorana particles would create.
The Delft group found the first indications of the Majorana particles at the ends of a partially superconducting microscopic thread of indium antimonide. Kouwenhoven has long been investigating such nanowires -- last year he received a grant of one million dollars of software maker Microsoft for his quest for the artificial-Majorana fermion. Even physics financier FOM put up one million.
Microsoft's interest stems from the possibility of computer memory with Majorana particles. Such a computer would not use 1 or 0 bit states; Instead, it will use quantum bits, which facilitate much more computation. The problem with such a quantum computer is that quantum bits are sensitive to disturbances. Pairs of Majorana particles form an exception. They can be disrupted, but owing to their special mathematical properties, they always spring back to their original state. That is a desired property for a robust quantum memory system.
In the research, each memory element comprises a nanowire of indium-arsenide in which two electrodes with the underlying quasi-particles produce so-called Majorana's. These are not sensitive to external disturbances causing an internal conditions change. The two Majorana on each of the elements form together a qubit. Qubits are the ones and zeros which allow a quantum computer to carry out numerous calculations simultaneously, instead of all the calculation steps one by one, as in conventional computers.
OK, Majorana Fermion is a particle for which a=a+
But by definition the second quantization operators [a,a+]=(aa+)-(a+a)=1
So we have a contradiction here, because if a=a+, then [a,a+]=0, which does not obey to the definition of second quantization operator.
Someone cares to enlighten me?
How do those Majorana a and a+ operators look in positional representation? How does the first wave function look like?
I'll try later to find original Majorana papers, but in meantime if you have some hints I'd be glad to hear.
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#\ @ ? Colonize Mars
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That's pretty close to TU Delft, so maybe the ones TU Delft has found are one of the pairs from Deltares?
At least I THINK that's what the Dutch speaking guide called them.
Are you saying the other ones were formed by magic?
Ever wonder why atomic weights vary from place to place?
No, because they don't. The mass of avagadro's number of carbon 12 atoms is the same - 12 grams - everywhere. The weight might differ due to G not being constant across earth but that's not exactly news either. And if atomic weights did depend on where you are in space, there's be all kinds of zomgwtf effects that would've been seen a long time ago.