All-Optical Networks: the Last Piece of the Puzzle 36
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by
Soulskill
from the light-at-the-end-of-the-tunnel dept.
from the light-at-the-end-of-the-tunnel dept.
Esther Schindler writes "An MIT professor explains why "simple" ideas require hard science and how a gemstone might be the key to an optical network. As the story begins: 'For years, the dream of an all-optical network has lain somewhere between Star Wars and a paper cup and a string. Recent successful work on the creation of an optical diode is a virtual case study in both the physics and materials sciences challenges of trying to develop all-optical networks. It is also a significant step towards their final realization.' One answer may be... garnet. Yes, the January birthstone. 'The material that Ross and others in her field use is a synthetic, lab-grown garnet film. Similar to the natural mineral, often used as a gemstone, it is transparent in the infrared part of the spectrum. This makes synthetic garnet ideal for optical communications systems, which use the near infrared. Unlike natural garnet, it's also magnetic. ... While it works, it's too big and too labor intensive for use as a commercial integrated chip. For that, you need to grow garnet on silicon. The challenge that Ross's group overcame is that garnet doesn't grow on silicon.'"
Re:Broadband cable? (Score:2, Informative)
Re:Broadband cable? (Score:5, Informative)
As for why this is a good thing, there's a difference between the speed of electrons through copper and silicon vs. the speed of light through translucent plastics and crystals. It should also run cooler.
Ive seen varying numbers that indicate that the difference is not as large as some are supposing.
This wikipedia article [wikipedia.org] seems to indicate that 82% for coax is possible, 72% for plenum cat 5.
From what I've read [wikipedia.org], and according to google calculations [google.com], the speed of light in optical fiber is about 66% of that in a vacuum. ( also supported here [stuartcheshire.org], and here, as a reciprocal [advaoptical.com])
In other words, copper is faster. There are certainly some benefits (removal of the interference factor, possibly running cooler, possibly lower power usage), but I dont believe signal propogation speed is one of them.
Re:A diode is not enough (Score:1, Informative)
Optical Transistors already exist.
http://spectrum.ieee.org/semiconductors/optoelectronics/optical-transistor-is-a-step-toward-the-quantum-internet was the second result on Google behind Wikipedia.
If you read the article, you'll see why diodes came last in this case - but then again, why read the article when you can just make uninformed comments?
Re:"Yes, the January birthstone." (Score:4, Informative)
http://en.wikipedia.org/wiki/Janus [wikipedia.org]