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Researchers Develop Photonic Processors
TheCybernator writes to mention a New Scientist story about scientists who are developing a light-based processor by actually storing and delaying photons. These 'optical buffers' may one day be used to make super-fast microchips based on light instead of electrons. From the article: "A decade from now ... there [may] be not seven cores but hundreds on a chip ... Connecting these cores using light could solve this problem. Until now, the lack of optical buffers has been a key roadblock to these kinds of light connections. The way information is transmitted means that buffers must hold packets of data while a router decides where they are to be sent. Buffers are also needed to delay optical pulses - so they do not collide at switching points - and to synchronise streams of data coming from different places."
Something like 20 years ago, I heard about a device that used interference in a crystal with the upshot that the presence of light on one facet of a crystal determined whether light could go through the crystal along another path. This was supposed to form the basis for entirely-optical logic devices. Does this ring a bell? Anyone?
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
If the ionization-rate is constant for all photonic entities, they can really bust some heads... in a optical sense of course.
I'd like to know how and with what form of computer science 100 CPU cores will be useful for.
Slashdot: Playing Favorites Since 1997
Cool! I should still be alive then!
Does this mean Santa will finally have time with the family?
The world market for photonic computers will only be five or six.
Another technology that sounds cool but we'll never see because we'll have to wait 20 years for ther patents to expire, before we see this be put into practice.
Whatever happened to Carbon Nanotubes?
... a New Scientist story about scientists who are developing a light-based processor by actually storing and delaying photons.
I'd be more impressed if they'd developed an optical processor that actually stored and speeded up photons.
The higher the technology, the sharper that two-edged sword.
silly question, silly answer.
Using light would let chips run at the speed of light! Or is that the speed of electricity? They both run at the same speed. What is the real benefit to using optical chips? Three dimensional optical storage I can see. Long distance cabling runs I can see. Transfers across tiny traces on a chip... not so clear to me. Especially considering the size increase that could be expected by moving to optics. Is it the same lack of attenuation seen in optical fiber at work on a small scale and making a noticeable difference when the effect is considered across billions or trillions of pulses? Will there be fewer heat problems when scaling the chips to higher speeds?
Or is this really just hype and they are really referring to optical equipment that will be used to route signals that are already on optical fiber runs without converting the signal to electricity and back?
Our researchers have developed a Photonic Processor. We don't know what it can do, but it sounds important enough. Maybe in a few hundred turns, we'll have a faster and more complex computational device to do faster and more complex calculations. Hopefully we'll develop Droid Sentries before the Drath Legion wipes out our civilization.
I guess the author didn't know 100+ core chips are already out, http://www.rapportincorporated.com/, with a 256 cored chip already for sale. They are already coming out with a 1024 cored chip. In fact, IBM has already entered a partnership with them creating a multichip, PowerPC core + 1024 cores for a 1025 cored chip.
Hopefully using light instead of electrons would cut down on the amount of heat that is dissipated. Otherwise, a 256-core processor could serve double duty as a furnace for a 3000 sq foot home in winter.
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There is inferior bacteria on the interior of your posterior.
There is no such thing as "speed of light inside a metal", because, you know, metals are pretty much non-transparent, as in, light does not propagate through them! If in doubt, find metal object and try to see through it! :)
"Speed of electricity" that GP was referring to was a cute (if not entirely scientfic) way to trick the reader into thinking that "speed of ligth" and "speed of EM wave" in given medium are somehow different -- nope, they are not.
Speed of E/M wave in SiO2 insulator between two sides of copper microstrip line and of light in fiber, made of the same SiO2 are exactly the same.
As to making fibers out of something with \epsilon about 1 (close to that of vacuum/air) -- you can not! Or, at least, it will stop working like a fiber you can route around, read some day about why optical fiber works.
Paul B.
..., unlike electrons. There goes your dream of an all-optical transparent switch. You can still control light with electrical signals, or reflect it with a MEMS micromirror, and I guess you can achieve total bandwidth in 100 terabit range right now -- what is problematic (especially with MEMS approach) is packets becoming too long: terabit with 1ms MEMS switch time -> gigabit packet.
= kkIVAAAAEBAJ&dq=bunyk /.nickname is not entirely accidental :) ).
Anyway, someone who really needs small packet switching at fiber speed in 100 terabits/sec might as well go with superconductor approaches (you do not expect such a router to fit into a single pizza box, right? You can integrate cooler in a rack easily) -- see, e.g., http://www.google.com/patents?vid=USPAT6917537&id
(correlation between inventor's name and my
Well, maybe one of these days...
Paul B.
Just a thought, but doesn't that mean that you could use superposition to your advantage.
I'm no expert on the intricacies of microprocessor design, but it seems to me that being able to re-use the most frequently used elements would be quite beneficial. This would cut down on a huge amount of circuitry. At the very least, physically the chip could be smaller.
At this point this is purely speculation on my part. Until someone figures out how to control photons with other photons (rather than electrically) the benefits will likely be offset by the extra support circuits required to control the logic gates etc.
You have just received the Amish virus. Since we have no electricity or computers, you are on the honor system.
Just a thought, but doesn't that mean that you could use superposition to your advantage.
:) ).
I'm no expert on the intricacies of microprocessor design, but it seems to me that being able to re-use the most frequently used elements would be quite beneficial.
Congratulations, you've just re-invented a quantum computer, really! Put a bunch of bits into quantum superposition state (starting calling them qubits from now on) and perform some operations on all at once.
Things like this do work well with (a couple of) photons, as a matter of fact they were shown to work -- though other techniques still work better (NMR, superconductor stuff -- but I can not talk about the latter
For fun, check this out: http://dwave.wordpress.com/
Paul B.
Functional programming is ideal for the kind of CPUs the article describes. 100s of computing tasks executing in parallel? a dream come true...
Doctor: "Arm The photonic cannon!".
So the OCPN research group here has already gotten our All-Optical packet-routing to work. All optical in that the signals is Never converted from Optical. The switching signals are still electronic, but an integral part of the system is the packet delay (so the signal is delayed while the switches are set).
We, at first, literally used strands of fiber to delay the signal (so a non-variable delay), now we're using the same fiber delay, but between the multiple strands of fiber are the typical 2x2 optical switch (like a Mach-Zender interferometer-based switch), allowing you to switch on/off various delay line segments (thus allowing you to choose the delay, so you can synchronize the incoming signal, etc.). For the next step we'll be integrating this system onto an InP chip (similar to what the article says has been done).
More importantly, what good is IndiumPhoside based technology if everything's made on Silicon??? John Bowers here, recently made the breakthrough in bonding InP to Silicon, paving the way for allowing this technology to actually become useful outside of the long-range communications industry!