Optical Fiber With a Silicon Core

Roland Piquepaille writes "According to the Optical Society of America, U.S. researchers have been able to create a practical optical fiber with a silicon core. As they were able to use the same commercial methods that are used to develop all-glass fibers, this might pave the way for future silicon fibers as viable alternatives to glass fibers. The scientists note that this should help increase efficiency and decrease power consumption in computers and other systems that integrate photonic and electronic devices. Here is a good summary by the lead researcher: 'In the past, we've needed one structure to process light and another to carry it. With a silicon fiber, for the first time, we have the ability to greatly enhance the functionality in one fiber.'"

Comments

Optical + Silicon + The Internet is for...?

[Syrente]

There's a boob joke in here, somewhere.

Re:Optical + Silicon + The Internet is for...?

[JCSoRocks]

There would be if people made breast implants out of a semiconductor.

Re:Optical + Silicon + The Internet is for...?

[FinchWorld]

There's a boob joke in here, somewhere.

Its slashdot, theres a boob joke everywhere.

Re:Optical + Silicon + The Internet is for...?

[Kaenneth]

You guys (Parent and Grandparent posters) are a couple of boobs.

Re:how is glass different than silicon?

[amRadioHed]

Actually, the underlined text in the summary is called a link. Click it and you will see what is called TFA. It actually explains some of the potential advantages of the silicon core.

Re:how is glass different than silicon?

[Anonymous Coward]

glass is silicon dioxide. Silicon is pure Si.

Good! Just what the doctor ordered!

[Yvan256]

More fiber!

Re:how is glass different than silicon?

[kmac06]

So is silicon, at for infrared wavelengths.

Re:how is glass different than silicon?

[ISoldat53]

From TA. "Usually an optical fiber is made by starting with a glass core, wrapping it with a cladding made from a slightly different glass, and then heating the structure until it can be pulled out into long wires. This works well enough, but for some wavelengths of light, a core made of pure crystalline silicon, like the one developed by the Clemson team, would better carry signals. Additionally, crystalline silicon exhibits certain nonlinear properties (in which the output is not proportional to the input) that are many orders of magnitude larger than for conventional silica glass. This would, for example, allow for the amplification of a light signal or for the shifting of light from one wavelength to another. The development of a silicon fiber opens the way for signal processing functions that are currently done electronically or in separate optical circuits to be performed directly inside the fiber, which allows for more compact, efficient systems."

Re:how is glass different than silicon?

[canajin56]

Glass is made from silica, which is silicon dioxide. This, on the other hand, is pure silicon crystal. So, it's different in many ways, just as aluminium is different from corundum. Although admittedly silicon crystals are closer to glass than a beer can is to a ruby.

How do they do it?

[tsa]

OK, I've read TFA. Now all I want to know is: how the hell do they make many many kilometres of crystalline silicon? Amorphous Si, OK, I can understand, but getting it crystalline is amazing. Or do they mean polycrystalline? Wouldn't that ruin the optical properties?

Re:How do they do it?

[MightyYar]

The silicon crystals they grow for wafers are huge these days. Presuming that they draw it out the same way that they do traditional fiber optic cable, they'll get plenty of length.

A BIG optical fiber is 100 microns across (0.1 mm). A big wafer is 300mm. So they stretch down over 3000 times in size, which should give you 9 MILLION times the original length, unless my math fails me. I don't know how long the crystal is that they grow these days for wafers, but one only half a meter long should go a long way at that diameter...

Re:How do they do it?

[mapsjanhere]

the wavers are actually sliced out of big single crystalline cylinders; making the cylinders bigger was what slowed the progress of waver growth. I don't think you can "draw" the crystal in a conventional sense, but since the material is extremely clean, it should recrystalize back into a single crystal out of the melt.

Re:How do they do it?

[smaddox]

I was wondering the same thing. Silicon is not a glass, and cannot be stretched like a glass can.

Glasses have very fuzzy 'melting points'. In other words, they just get gooey rather than becoming a liquid. Silicon on the other hand, has a well defined melting point, and is not gooey.

Now, silicon crystals ARE grown inside of SiO2 lined graphite crucibles. So, I imagine that they might be able to melt the silicon inside of a Si02 layer, and stretch both. Then, when it cools, the silicon will form microcrystals. So, it wouldn't be crystalline, but it would still be transparent to photons with energy below 1.1 eV (wavelength greater than 1.1 um).

I think his question was fair...

[PortHaven]

I read the article and even did a quick google and did not gain any insight.

However, a Slashdotter replied to his question:

"glass is silicon dioxide. Silicon is pure Si."

And now I have learned something...woo-hoo!!!

Re:ohnoitsroland!!

[clem]

I don't see how unfair it is that Roland Piquepaille should receive compensation for what effectively is online research. It's at least as fair as Slashdot, a for-profit company, getting loads of free online research from article submitters.

How do you lose out by his $80 an article?

Re:ohnoitsroland!!

[Ethanol-fueled]

He copies-and-pastes the meat of his journal entries from professional and academic journals and news magazines

Some mods call this "karma whoring", but this is slashdot, and who wants to navigate through 10 pages just to RTFA when half of the participants don't even read the fuckin' articles? :)

Re:Just How I Like My Women

[khellendros1984]

Going after the robo-ladies, AC?

Cheaper net for the aussies

[afidel]

The first thing I think of when I hear increased efficiency is not "oh great now my GBIC's will save a few mW of power" it's "that's great for international communications". The reason is a big part of the cost of an undersea cable is the boosting equipment and the weight and bulk required to provide power to them.