Researchers create laser light interconnects on silicon

Only a few years ago there was a holographic storage device that, had it been built, would have stored a massive 100GB. Overtaken by history. Again.

--
Dirk

http://www.onetribe.me.uk/wordpress - The UK\'s only occult talk show
Presented by Dirk Bruere and Marc Power on ResonanceFM

Intel is like Microsoft. They stumbled onto a big thing by accident, and interpreted the event as skill. And everything else they try doesn't work.

John

John Bowers of UCSB is a collaborator of mine...we're on the Intra-Chip Optical Networks (ICON) team in the DARPA UNIQ program. He's a very smart guy who knows his stuff, and this is a pretty nice piece of work. However, he's not the one doing all the heavy breathing--it looks like the Intel hype machine is what's behind that. (Those Intel hype guys are _good_--better than the technology people, that's for sure.)

The gee-whiz terabit numbers are assuming things like 40 Gb/s per wavelength, with 50 wavelengths per line, which isn't impossible at all. The idea is that one 'wire' can pass many full-speed logic signals simultaneously, which is a big win. You don't need terahertz logic speeds to do this, which is a good thing since we're not going to have terahertz logic speeds, ever.

You need a transistor f_max at least 10 times the logic speed, and you can't make transistors with f_max of 20 THz. This is because the maximum frequency that signals can propagate in a semiconductor is proportional to the square root of the carrier density. The same is true in plasmas, which is why this limit is called the 'plasma frequency.' You can't dope semiconductors enough to get the plasma frequency higher than 10-30 THz, so you can't make 20 THz transistors, so you can't make 2 THz logic out of transistors. Not to mention that at that speed, the region of the chip you can keep synchronous is about

30 microns square, on optimistic assumptions.

It's very helpful to have optical gain in all-photonic ICs, and these InP-based devices may turn out to be an important part of the tool kit. Wire is so much easier to make than these optical gizmos that we have to have a really amazing advantage in real computer performance before the chip guys will even talk to us. (I'd feel the same in their shoes.) Fortunately it looks like we can do that.

Cheers,

Phil Hobbs

Lots of 40GB/s channels down one optical waveguide does sound interesting - serial busses are cute, and a multiplexed otpical serial bus would be just that much cuter.

--
Bill Sloman, Nijmegen

I heard about it for mass storage for the Illiac-IV, about that time. The real question is "why bother"? S/N of the media is the limiting factor.

--
  Keith

That's what they get for trying to maintain backward compatibility to the 4004 processor.

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Now, that's good thinking:-)

Mati Meron | "When you argue with a fool, snipped-for-privacy@cars.uchicago.edu | chances are he is doing just the same"

"Data is recorded at 1.4 million bits per second, using a blue laser from

405 to 407 nm in wavelength."

That's truly impressive, man! Almost as fast as 1x CD recorder! Only 19 days to write a 300 GB disk.

It's everywhere: newspapers, NPR radio, all the electronics web sites. And they all, to various and usually severe degrees, get the technology all tangled. Some of the bloopers I've heard include...

Calling it silicon lasers

Saying it will speed up chip-chip interconnects because light propagates faster than electricity

Signals are fast on-chip but slow down between chips

Laptops get hot because of signals heating wires inside

This will be practically applied by the end of this decade.

"Lasers are already used to transmit high volumes of computer data over longer distances ? for example, between offices, cities and across oceans ? using fiber optic cables. But in computer chips, data moves at great speed over the wires inside, then slows to a snail?s pace when it is sent chip-to-chip inside a computer."

- the New York Times

John

Adult Swim on cartoon network?

There have been many: fiber optics, CDs and DVDs, CCDs and thermal imagers, semiconductor lasers, laser printers, high-efficiency LEDs from infrared to ultraviolet. But Intel hypes every obscure gadget as the Next Big Thing, like their Raman "on-chip silicon laser" that needs a table-sized external optical pump.

Pasting compound-semi lasers on top of silicon chips is interesting, worthy of a journal article, but everybody is already declaring it to be a miracle that will change the world. Unlikely.

John

Could fit on the head of a pin.

On a sunny day (Mon, 18 Sep 2006 19:42:53 -0400) it happened George Macdonald wrote in :

Your remarks, you are proven wrong, and do not admit it.

Time to killfile your drivel.

On a sunny day (Tue, 19 Sep 2006 03:11:04 GMT) it happened "Alexander Grigoriev" wrote in :

Yea, that is a good point. But it took longer to make the movie. Anyways from 1x CD-R to 32x CD-R took only a few years.... and 32x was the limit because of centrifugal force, so as he had his 30 years, the next few years should give exponential speed increase. It is quite common for video render farms to run for days anyways.

But you could burn to blue-ray too. However when you look at data carrier volume, this thing wins. Say library of congress, how much space needed. Storing in New York is more expensive then on the land ;-) maybe use these things mainly in cities.

On a sunny day (Tue, 19 Sep 2006 03:11:04 GMT) it happened "Alexander Grigoriev" wrote in :

Yea, that is a good point. But it took longer to make the movie. Anyways from 1x CD-R to 32x CD-R took only a few years.... and 32x was the limit because of centrifugal force, so as he had his 30 years, the next few years should give exponential speed increase. It is quite common for video render farms to run for days anyways.

But you could burn to blue-ray too. However when you look at data carrier volume, this thing wins. Say library of congress, how much space needed. Storing in New York is more expensive then on the land ;-) maybe use these things mainly in cities.

interconnects.

Well, I was not insulting anyone. You would not happen to be a Muslim fundamentalist now would you? They get insulted by a self-inflicting reflective suicide-insult mechanism. like this:

'Moslems Threaten to Massacre Christians Over Claim of Islamic Violence'

LOL

On a sunny day (Tue, 19 Sep 2006 05:38:55 -0400) it happened Trent wrote in :

Not many angels could fit on your pin.

No, they fail *miserably* every time they try yo break that compatibility (e.g. iAPX-432, i960, Itanic). Compatability *is* their one-trick pony.

--
   Keith

It's a spoof of the original, Sealab 2020. They take the original animation and dub in new dialog for comic effect.

After they succeeded the guys doing it obtained high-end editing stations and a budget such that, in more recent seasons, there's lots of entirely new animation and much more "slicing and dicing" of scenes (part of the genius of the initial seasons was that the animation ran pretty much the same as the original, uncut) -- the fact that some of the scenes still came from Sealab

2020 no longer seems like a significant part of the episodes, which to me makes them nowhere near as good as the first couple of seasons.

Amazon.Com would be happy to sell you the DVDs; it's on late at night on the Cartoon Network in the US.