Physicists Successfully Carry Out Controlled Transport of Stored Light (phys.org) 39
schwit1 shares a report from Phys.Org: A team of physicists led by Professor Patrick Windpassinger at Johannes Gutenberg University Mainz (JGU) has successfully transported light stored in a quantum memory over a distance of 1.2 millimeters. They have demonstrated that the controlled transport process and its dynamics has only little impact on the properties of the stored light. The researchers used ultra-cold rubidium-87 atoms as a storage medium for the light as to achieve a high level of storage efficiency and a long lifetime. The controlled manipulation and storage of quantum information as well as the ability to retrieve it are essential prerequisites for achieving advances in quantum communication and for performing corresponding computer operations in the quantum world. Optical quantum memories, which allow for the storage and on-demand retrieval of quantum information carried by light, are essential for scalable quantum communication networks.
In their recent publication, Professor Patrick Windpassinger and his colleagues have described the actively controlled transport of such stored light over distances larger than the size of the storage medium. Some time ago, they developed a technique that allows ensembles of cold atoms to be transported on an 'optical conveyor belt' which is produced by two laser beams. The advantage of this method is that a relatively large number of atoms can be transported and positioned with a high degree of accuracy without significant loss of atoms and without the atoms being unintentionally heated. The physicists have now succeeded in using this method to transport atomic clouds that serve as a light memory. The stored information can then be retrieved elsewhere. Refining this concept, the development of novel quantum devices, such as a racetrack memory for light with separate reading and writing sections, could be possible in the future. The findings have been published in the journal Physical Review Letters.
In their recent publication, Professor Patrick Windpassinger and his colleagues have described the actively controlled transport of such stored light over distances larger than the size of the storage medium. Some time ago, they developed a technique that allows ensembles of cold atoms to be transported on an 'optical conveyor belt' which is produced by two laser beams. The advantage of this method is that a relatively large number of atoms can be transported and positioned with a high degree of accuracy without significant loss of atoms and without the atoms being unintentionally heated. The physicists have now succeeded in using this method to transport atomic clouds that serve as a light memory. The stored information can then be retrieved elsewhere. Refining this concept, the development of novel quantum devices, such as a racetrack memory for light with separate reading and writing sections, could be possible in the future. The findings have been published in the journal Physical Review Letters.
Coming to a store shelf near you (Score:2, Funny)
Re: Coming to a store shelf near you (Score:2)
I had this image of our heroes from Planet Express delivering a crate to some dark planet, and Fry accidentally dropping it, and of course it breaks.
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Physically moving a cloud of atoms (Score:2)
IANAP but it sounds like instead of moving around magnetic bubbles on a surface or magnetic domains on a nanowire, they are *physically* moving clouds of atoms? I wonder how quickly you can move a cloud of atoms since that would
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Wait, light travels at light speed?!
(mind blown)
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Read what the scientists wrote. They are moving clouds of atoms in which light is "stored". Speed of physically moving something would appear to have an impact on switching speed.
Which isn't as impressive (Score:2)
Though it doesn't even really seem that they're storing light so much as getting atoms to emit a photon with properties nearly identical to those of photons used to excite them. As cool as that is, it sounds a lot more like recording than storing. Recording in a medium that lacks the benefits of light - like that whole really really fast thing.
Distance (Score:2)
A journey of a thousand kilometres begins with the first 1.2 millimetres.
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Not in this case. Difficulty goes up super-linear with distance here, likely exponentially. It is quite possible that there is a pretty hard wall somewhere around a few meters.
This is nice research and it may serve to find out more about this physical universe, but there are zero practical applications and the exceptional success of conventional networks (or conventional computers) will not be repeated.
An idea and a question... (Score:2)
Couldn't we just not move anything at all?
What if we had multiple sets of entangled particles, entangled so that for every particle we would otherwise move, there would be an entanglement over that distance instead.
Then if we input the input data at, you guessed it, the input particles, the output would "instantly" appear at the output particles. Of course the information would still not progress faster than light, BUT: If my feeling is right, it would not matter what paths it took outside of our event cone
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Well, if you figure out how to do this little part, there is a nobel prize waiting for you.
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That was done as a satellite communication experiment 20 years ago.
And yes, the information is transmitted "instantly".
The problem is having enough entangled particles, being able to measure them without breaking entanglement and sending somewhere without breaking entanglement.
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That is called: an education.
Some countries provide a general education.
Actually not only some countries, but it is very common in Europe.
If you lack such a general education, blame your school system and not the messenger.
And yes: considering the low standard of actual knowledge on /. I'm indeed an expert on everything. Sad, isn't it? Here in my countries, I'm only considered a "well read fellow".
Have a ice day.
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If you would say, what kind of paper, I surely could link you some :P
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Well, then we have at least one point to disagree on :P
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Actually, we had basic nuclear physics in school, oops.
And I studied physics in University, oops.
And "rocket science" is in many regards a very simple topic, oops, e.g. orbital mechanics. Obviously I do not know out of my mind which shape of an exhaust tube of a rocket engine is better for non atmosphere or earth atmosphere.
I never claimed I had a clue about brain surgery, beyond the "basics" which everyone can/should have learned in school. Sorry.
Point is: half of the ppl here have no education regarding a
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sending somewhere without breaking entanglement
FedEx. I ordered a set of earbuds and the cord was hopelessly entangled.
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LoL :P
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640K cubits is enough for anybody.
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And that has _what_ relationship to communication networks exactly?
As an aside, there will exceptionally likely never be 640k effective qbits. If they fake the computations, they are at around 50 today. If they run actual computations where a QC would be faster, they are at zero. The entanglement is lost long before they get anywhere.
Time, not distance (Score:2)
For what duration were they able to store this light while transporting it? That would seem to be of equal interest. I mean if I want to transport light 1.2 millimeters, I just shine it down a 1.2 millimeter fiber. Job done. Storage would seem to be the Holy Grail, as that allows things like delay lines, shift registers, memory and all the other goodies that make computers useful things.
TFA sounds like interesting stuff being done with Bose-Einstein condensates. But that isn't mentioned. So is their cloud
Professor Patrick Windpassinger (Score:2)
"slow glass" (Score:4, Informative)
Reading this summary, I couldn't help but think of one of the best SF stories I've ever read: "Light of Other Days, by Bob Shaw: https://en.wikipedia.org/wiki/... [wikipedia.org]. Thoroughly recommended. (I found a copy here: https://www8.physics.utoronto.... [utoronto.ca]). This is NOT the Arthur C. Clarke novel, "The Light of Other Days".
Old news (Score:2)