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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."
It may be slightly IO bound, but we could always use a microwave bus and solid state memory and AGP 16X graphics cards. Plus with a huge amound of cache (say 16MB) the computer would be really fast without too many bottlenecks.
found here
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.
It isn't Copernicus' equations that are used for spacecraft, but Newton's F=ma, Newton's law of gravitation, and an occasional use of General Relativistic corrections.
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
Moderators, quantom technology has been connected very closely to time travel. For more information look at any quantum book. I would suggest Stephen Hawkings old book, A Brief History of Time.I dont have Mod points anymore so I cant correct this.
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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.
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No, here's what you need. You take a microwave transmitter and blast a second or so of bits at the moon. Wait three or four seconds, it echoes back. Receive it. Correct the errors (you did use error-correcting code, didn't you?), then send it to the moon again. And when it echoes back transmit it again. And so forth. First trick: you can correct and retransmit simultaneously with the reception. So you can have more data in flight than you have memory for on Earth. Second trick: you'll note that the power you get back is far less than what you sent out. But you can still retain the data. You have to act as a repeater, but that's all.
You could do this with mirrors, but the mirrors will probably be too close together to store very much. Still, a laser, and a nearly 90 degree angle, and the light will zig-zag a lot, and you might have a few hundred feet before you need a repeater. Damned dusty mirrors! Damned non-transparent air!
Third trick: with the moon, you now have a sort of bubble memory, but it's over 100,000 miles long. You could do the same trick with 100,000 miles of fiber-optic cable. But if you could slow down the speed of light you could use shorter cable (or store more in the same cable without having to drive the frequency and the bit rate really high). Also, you could shorten the period, which means your data is available sooner.
If you can really slow down light to a few cm per second, then you can store a lot of stuff. But you will need power for the repeating.
(What would be better is to make windows out of this stuff. You could look out the window and see what was happening outside yesterday. But imagine the solar power applications if you made the glass twelve hours thick instead of twenty-four. Sunlight would shine in during the daytime, and come pouring out at night!)
Sunlit World Scheme. Weird and different.
The article gives the impression that these chips are storing or freezing light. I dont see how this is possible. If they were truly "storing" light how would one know? The way I see it, is that if you can "see" or "observe" light then by definition the light must be escaping.
A better way of describing what this stuff does is that it records the state of the wave at every point in the medium. When they want to regenerate it, they recreate the pulse using that information. Effectively, all they're doing is recording the 3D information that they need to recreate the pulse, almost like a hologram.
The pulse is not actually still in the system while it's "frozen" - the energy has dissipated, and the record of its state is all that's left.
Remember, when light moves through a substance, you're not dealing with a continuous solid indivisible "thing" that remains unchanged. When photons move through glass, they get absorbed and re-emitted billions of times before they finally come out the other side.
Coming soon - pyrogyra