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Storing Light In Chips
Roland Piquepaille writes "Recently, researchers have "stopped light" by storing light pulses in hot or extremely cold gases (check these former stories on Slashdot or at BBC News Online). Now, scientists from Stanford University have devised a method to store light pulses under ordinary conditions. In Light-storing chip charted, Technology Research News says this opens the way for all-optical communications switches, quantum computers and quantum communications devices. The researchers plan to demonstrate this technique by trapping microwave signals within a year. They think that a prototype which works at optical frequencies could be made in two to five years. This overview contains more details and references."
This was predicted by Schrodinger in the 30's - it really took them a long time to do it.
Storing microwaves within a year isn't very hard. I mean a year is huge!
Well, if the light is held, it's not getting to your eyes, and thus not making a visible picture. So in that particular instance, I would think that this wouldn't help very much.
Karma: Contrapositive
quantum computers are still, and will be, a very very long way off. it is not enough to say that one single development will speed their coming, rather one obstacle will be replaced by another - sod's law
tim
I'm wondering if light or other waves stored in such a fashion could be used as a battery of sorts.
Paul Lenhart writes words!
When can we step back into the past and correct someone else's mistakes?
Anything in parenthesis may (not) be ignored.
Does this sound like another one of those "breakthroughs" in optical/quantum computation where prototypes are "just around the corner" and commercialization is "just a few years away", yet it never happens?
Tell me how this time it's different. Does it work on standard fab processes?
I would really love a CPU with a terahertz clock. I guess it would still be I/O bound, though.
I wonder if optical will simply be bypassed by other, already denser technologies. Semiconductor feature sizes are an order of magnitude smaller than a wavelength of light -- giving them at least a 100-fold advantage (assuming the an optical computer could even have useful feature sizes at wavelength scales). Commerically available HD densities are over 100 bits per micron-square. And this does not even count on any new nanotechnologies in circuits or storage.
I'm sure that optical will have a role in the future. The ability to send ultrahigh bandwidth signals over long-distance fibers is extremely valuable. All-optical switching/routing would certainly improve latency. The ability of light beams to nondestructively pass through other light beams also makes it ideal for denser chip-to-chip and device-to-device interconnects. Finally, holographic memory storage migth have a future (although it would not surprise me if current HD densities are probably on par with expected future holographic information densities)
That's why I doubt that we will see an all-optical future. Other technologies already provide better densities in circuits and storage. Only in the realm of communications, does optical really shine.
Two wrongs don't make a right, but three lefts do.
This seems like a step in the right direction. I wonder if it can be used for memory or just buffers of a sort. Don't get me wrong, I don't think anyone expects a transition from electrical computers in the next decade, but the breakthroughs on the optical front seem to be accelerating.
I do security
Yeah I was excited reading the article until this quote.
"The work would have been more impressive had the authors demonstrated the stopping of light experimentally, he added." Raymond Chiao, a professor of physics at the University of California at Berkeley.
Yup one of those 2-5 years things again, like so much else...
That's wrong on a lot of levels: LCDs do not store light, they selectively block it. Liquid Crystals (that give LCDs their name) do not stay in a fixed state on their own, but must be regularly aligned. Small and old displays use scanning very similar to CRTs, modern and large displays have a memory cell for each pixel.
What I think about is the future ability to create custom and finely tuned diamonds with different amounts of "impurities" grown into it with .30nm amounts of detail.
What if you can not only use diamonds for electronic media, but also use the refractive nature of diamonds for storing and moving light?
Couldn't the different light "switches" and other networking technology be added into diamonds as they are grown?
Could you use something like that to grow 3 dimensional computer chips and storage media?
Also aren't diamonds pretty much destruction proof... could you were a future computer in a ring or a harddrive in a earing?
Yes, the concept (it is only a theoretical concept, not a chip, in the paper) does store the light. When the optical pulse is completely within the postulated structure (meaning only a very short pulse can be stored), a modulation of the refractive index causes the fields associated with the pulse to be stored in the internal cavities of the crystal. Reversing the refractive index change causes the stored fields to reform a traveling wave, which exits the structure. The way that you know that the pulse has been stored in the computer simulations is that after the first refractive index change, nothing comes out of the structure. After the second change, a pulse emerges that has the same shape as the one that was sent in.
If you had just looked at some links in your Google search you would have found this:
To be precise, what we usually call the "speed of light" is really the speed of light in a vacuum (the absence of matter). In reality, the speed of light depends on the material that light moves through. Thus, for example, light moves slower in glass than in air, and in both cases the speed is less than in a vacuum. Link
I have been storing light in my fridge for years. Even when it's dark outside and I check, it is still there...
Light is just energy. Think about when light passes through glass. Do you think it just stops on one side and then appears suddenly on the other side out of nowhere? The molecules in the glass store the energy of the light, then pass it onto the next molecule. Therefore for a very short amount of time that molecule stored the light. But what seems to have been done here, is that the scientists were able to keep the molecules in that excited state for a longer amount of time. BTW I did not RTFA, used to be a Phys Eng major.
Vote for new mod!!! Score:-2,Imbecile