New Material Sets Stage For All-Optical Computing

An anonymous reader writes with this excerpt from the International Business Times: "Researchers have made a new material that can be used to guide waves of light, a breakthrough that could lead to ultra-fast computing. Georgia Tech scientists are using specially designed organic dyes that can process and redirect light without the need to be converted to electricity first. ... 'For this class of molecules, we can with a high degree of reliability predict where the molecules will have both large optical nonlinearities and low two-photon absorption,' said [Georgia Tech School of Chemistry professor Seth] Marder." According to the article, using an optical router could lead to transmission speeds as high as 2,000 gigabits per second, five times faster than current technology.

Similar stuff from IBM

[distantbody]

EETimes has "IBM Research claimed a keystone achievement in on-chip optical communications Wednesday (March 3), saying its 40-gigabit-per-second (Gbps) germanium avalanche photodetector completes what it calls the nanophotonic toolkit." (link) [eetimes.com] (A few days before announcing 2,500 layoffs, hmmm...)

...And the same news from Semiconductor Intl [semiconductor.net].

Optocouplers

[derGoldstein]

I'd like to benchmark this against graphene [technologyreview.com]. Since optical signals don't have to be converted to electrical first, then (I think) the bottleneck would be the optoelectronics.

Power & Heat

[CraigoFL]

It's funny... when the tech industry first started talking about switching to light instead of electricity for the chip insides, the biggest motivating factor was speed. How much faster (usually determined in "clock" speed even) can we make a chip if we can use photons instead of electrons? These days, I'm more interested in other factors:

• How much electricity (per unit of performance) does it use?
• How much heat does it put out?
• How much smaller can we make the chip and its supporting components?

This is a result of the highly-clustered, highly-mobile computing age we live in today. A single fast chip isn't as applicable any more. Give us tiny and low-power.

Probably not much to see here, at least yet

[Curmudgeon420]

The big issues in designing optical switches is their switching time and minimum switch pulse width. I and my group built what is probably the first all-optical computer in the early '90s. We used Lithium Niobate switches, which limited the machine's clock frequency of 100 MHz. It's hard to find the original article, which is in the Feb. 18 issue of Science Express. Subscription required, unfortunately. In that article the authors say nothing about switching time, or minimum switch pulse. It looks like a good piece of research, but eons away from anything practical.