Graphene

[INRM]

New wonder material, one-atom thick, has scientists abuzz
URL: http://news.yahoo.com/s/mcclatchy/20090708/sc_mcclatchy/3268145

WASHINGTON — Imagine a carbon sheet that's only one atom thick but is stronger than diamond and conducts electricity 100 times faster than the silicon in computer chips.

That's graphene, the latest wonder material coming out of science laboratories around the world. It's creating tremendous buzz among physicists, chemists and electronic engineers.

"It is the thinnest known material in the universe, and the strongest ever measured," Andre Geim , a physicist at the University of Manchester, England , wrote in the June 19 issue of the journal Science.

"A few grams could cover a football field," said Rod Ruoff , a graphene researcher at the University of Texas, Austin , in an e-mail. A gram is about 1/30th of an ounce.

Like diamond, graphene is pure carbon. It forms a six-sided mesh of atoms that, through an electron microscope, looks like a honeycomb or piece of chicken wire. Despite its strength, it's as flexible as plastic wrap and can be bent, folded or rolled up like a scroll.

Graphite, the lead in a pencil, is made of stacks of graphene layers. Although each individual layer is tough, the bonds between them are weak, so they slip off easily and leave a dark mark when you write.

Potential graphene applications include touch screens, solar cells, energy storage devices, cell phones and, eventually, high-speed computer chips.

Replacing silicon, the basic electronic material in computer chips, however, "is a long way off . . . far beyond the horizon," said Geim, who first discovered how to produce graphene five years ago.

Sounds very interesting. Is it stronger than diamond at one molecule thickness? Or is stronger simply by weight?

Have we ever manufactured anything else that is literally only one molecule thick?

The Pentagon is also interested in this new high-tech material. The Defense Advanced Research Projects Agency is spending $22 million on research to make computer chips and transistors out of graphene.


Interestingly,
URL: http://en.wikipedia.org/wiki/Graphene

In May 2009 a team from Stanford University, University of Florida and Lawrence Livermore National Laboratory announced they have created an n-type transistor, which means that both and n and p-type transistors have now been created with graphene

Regarding Stanford University, University of Florida, Lawrence Livermore National Laboratory and DARPA's research on graphene chips and transistors...

How much faster would anyone here guesstimate that a computer made with graphene computer chips and transistors be over current supercomputers?

Keep in mind the chips would be very thin and small, the transistors probably wouldn't have to be too big, and it's electrical conductive properties.


INRM

[wackyvorlon]

This sounds like typical science reporting. Someone makes an advancement that is genuinely nifty unto itself, then a science reporter who only understands about half of it starts to blow it completely out of proportion. In the end, what the article predicts has no relation to what the advancement actually means.

It's become sufficiently hyperbolic these days that I don't bother to read any science news any more.

[Molinaro]

I didn't see any comments quoted by the OP that contradict the paper I read last night on Physical Review Letters.

http://physics.aps.org/viewpoint-for/10.1103/PhysRevLett.103.025301

[Myriad]

Oh, just what I need. Electronic devices with components one atom thick. Because the ones I use now aren't fragile enough.

"We've diagnosed the problem, sir. Your laptop's display screen has a bad molecule. It happens sometimes, what with quantum uncertainty and all. It'll need to be replaced, that'll be $.0000001 for the materials and $799 for labor. No, I'm afraid it's not covered under the warranty, you've voided the warranty by being less than five meters away from the thing."

Respectfully,
Myriad

[blutoski]

Have we ever manufactured anything else that is literally only one molecule thick?

Molecules.



Also: contrary to the gist of the article, graphene isn't a very-very new substance. It was first synthesized in 2004, and of course, it occurs naturally and has been isolated from graphite for ages.

A transistor was built a year ago: [http://news.bbc.co.uk/2/hi/technology/7352464.stm]

A paper from last December: [Operation of Graphene Transistors at GHz Frequencies (http://arxiv.org/abs/0812.1586)]

[drkitten]

Have we ever manufactured anything else that is literally only one molecule thick?

All the time. Soap films, for example.

[INRM]

So would you say that if computer chips and transistors were made out of this stuff that it could be millions of times faster or more so, than a regular silicon chip?

[drkitten]

So would you say that if computer chips and transistors were made out of this stuff that it could be millions of times faster or more so, than a regular silicon chip?

Probably not. Conductivity isn't the primary determinant of transistor speed. On the other hand, it would probably do marvelous things for power consumption and therefore battery life....

[Christian Klippel]

From my understanding, the "problem" of making chips faster isn't so much the material used, but instead stuff like wiring (internally un the chip as well as external) and power consumption.

Regular transistors (that is, bipolar ones) need a current to flow in or out of it's base to keep up the conductive state. So that's virtually a no-go for fast chips. Therefore we use FET's (field effect transistor), which don't require a current, but only a voltage. However, there is a capacitance at the gate (the switching input of a FET) that needs to be charged/discharged whenever the state has to change. This needs energy. The faster you switch, the more energy you need to put in or dissipate to charge/discharge that capacitance.

I guess that even with a new material the same problems will exist. Also, you can't make structures on a chip arbitrarily small. Even nowdays they need to use light with very short wavelengths, and use some optical tricks to get modern structures (which are smaller than the wavelength) onto the chips.

Even if you have a material that allows for atom or molecule sized structures, you still have the problem of actually reproducing these structures reliably to have any commercially usable application.

My personal guess is that the next big step upwards in speed will be by implementing optical elements (switches, "wires") instead of electrical ones.

Greetings,

Chris

[paximperium]

I can't wait till we get them diamond transistor chips.

[CelticRose]

This is old news. I first read about this in the Apr. 2008 issue of Scientific American, a magazine I stopped subscribing to because its articles tended to be out of date or biased. intro to article (http://www.scientificamerican.com/article.cfm?id=carbon-wonderland)

I found the method of producing the stuff to be quite amusing. They tried just about every way they could think of to make graphene: chemicals, writing with nano-pencils, etc. Eventually, they were able to do it by pulling the layers apart with sticky tape! :D D.I.Y. Graphene (http://www.scientificamerican.com/article.cfm?id=diy-graphene-how-to-make-carbon-layers-with-sticky-tape)

[Toke]

Here are some more materials (http://www.cracked.com/article_17476_7-man-made-substances-that-laugh-in-face-physics.html)

[INRM]

Toke,

Why would doctors want to make cameras out of elastic conductive material that could be fitted in the back of an eyeball?

(It was #4 on the list)

[Toke]

Toke,

Why would doctors want to make cameras out of elastic conductive material that could be fitted in the back of an eyeball?

(It was #4 on the list)

That makes the the tracking teams more discret while record your actions.

[soylent]

I, for one, welcome our new sp2 hybridized overlords.

[Normal Dude]

That makes the the tracking teams more discret while record your actions.

Dangit, you beat me to it...

I'm against graphene. After all, it could be used in government robots to enslave us and take our liberties. Or something.

[rsaavedra]

My personal guess is that the next big step upwards in speed will be by implementing optical elements (switches, "wires") instead of electrical ones.
Or maybe memristors (http://forums.randi.org/showthread.php?t=147928).

[INRM]

Toke,

That makes the the tracking teams more discret while record your actions.

Very funny.

Seriously, though, why would doctors want to do that? (I'm simply saying this because it was mentioned in the link you provided)

[Toke]

I guess that a camera tracking with the eyeballs could have some uses.
Anyway there is a long way from a micro camera to a functional cyborg.

It wont be doctors building the cameras, but they may use them for surgery before they start on the cyborgs.

[INRM]

Toke,

How bizarre...

[arthwollipot]

I can think of many reasons for wanting to record someone's visual field.

[Ziggurat]

Probably not. Conductivity isn't the primary determinant of transistor speed.

But it isn't the conductivity of graphene which is so remarkable, it's the fact that the electrons themselves move so damn bloody fast. The mobility is just huge. So in principle, the upper limit for graphene transistor speeds should indeed be considerably faster.

On the other hand, it would probably do marvelous things for power consumption and therefore battery life....

Actually, it might not, because the leakage currents in the off state are high. In other words, they aren't resistive enough when off. So you've actually got it backwards, at least for now: we expect possibly huge speeds, but will have to work hard to get efficiency in line. If we can get a commercializable fabrication technique off the ground (not a given either).
http://www.technologyreview.com/computing/20119/

[Jungle Jim]

Here is an update:

Two Win Nobel for Work on Ultra-Thin Material
http://www.nytimes.com/2010/10/06/science/06nobel.html?_r=1&hp

[Mister Earl]

I'm saving my radio-shack gift card for when they finally mainstream quantum computing.

[technoextreme]

Molecules.
Also: contrary to the gist of the article, graphene isn't a very-very new substance. It was first synthesized in 2004, and of course, it occurs naturally and has been isolated from graphite for ages.

A transistor was built a year ago: [http://news.bbc.co.uk/2/hi/technology/7352464.stm]

A paper from last December: [Operation of Graphene Transistors at GHz Frequencies (http://arxiv.org/abs/0812.1586)]
Your wrong. Graphene was only isolated in 2004 using scotch tape and tweezers. It was not synthesized. Synthesis only came after we realized that the stuff actually won't self destruct. Before 2004 that scientists weren't even sure if the material would remain stable once you isolated it.
Probably not. Conductivity isn't the primary determinant of transistor speed. On the other hand, it would probably do marvelous things for power consumption and therefore battery life....
I believe size is actually becoming more of a detriminant than conductivity.

Actually, it might not, because the leakage currents in the off state are high. In other words, they aren't resistive enough when off. So you've actually got it backwards, at least for now: we expect possibly huge speeds, but will have to work hard to get efficiency in line. If we can get a commercializable fabrication technique off the ground (not a given either).
http://www.technologyreview.com/computing/20119/
We really shouldn't expect huge speeds at this point. Graphene itself has two main problems. First of all as you point out there is no reliable fabrication technique that doesn't involve scotch tape. Second of all it actually is a horrible semiconductor in its present state. You actually have to dope the thing and to introduce a bandgap. So yeah its possible that we could get huge speeds but we are really in the infancy of working with this material.

[Olowkow]

Here is an update:

Two Win Nobel for Work on Ultra-Thin Material
http://www.nytimes.com/2010/10/06/science/06nobel.html?_r=1&hp

It is not only the thinnest material in the world, but also the strongest: a sheet of it stretched over a coffee cup could support the weight of a truck bearing down on a pencil point.

I'm having trouble believing that.

[Ririon]

I'm having trouble believing that.
Yeah. The pencil and the coffee cup would both shatter long before that could be demonstrated...

[Olowkow]

Yeah. The pencil and the coffee cup would both shatter long before that could be demonstrated...

Plus, the duct tape securing the membrane would fail.:D

[Hellbound]

Plus, the duct tape securing the membrane would fail.:D

Krazy Glue. It'll hold an elephant, how hard can a truck be?

:D

[Ririon]

It is not only the thinnest material in the world, but also one of the strongest. If scaled up to the thickness of plastic refrigerator wrap, a sheet of graphene stretched over a coffee cup could support the weight of a truck bearing down on a pencil point, according to tests conducted by two Columbia University researchers, Jeffrey Kysar and James Hone.
I think the article was updated with yet another super-material. :)

[Olowkow]

I think the article was updated with yet another super-material. :)

Wow! They must be monitoring JREF in real time! That has been added in the last hour or so. Nonetheless, it is still a remarkable claim...a little more believable now though. That would make some pretty cool bullet proof sports wear.

How could you cut it?

[Soapy Sam]

Carbon steel scissors?

If it could ever be produced in large scales it would have interesting effects on aircraft design- hyperlights? Dirigibles?

[John Jones]

I think the article was updated with yet another super-material. :)

Unobtanium?:)

[quarky]

Oh, just what I need. Electronic devices with components one atom thick. Because the ones I use now aren't fragile enough.

"We've diagnosed the problem, sir. Your laptop's display screen has a bad molecule. It happens sometimes, what with quantum uncertainty and all. It'll need to be replaced, that'll be $.0000001 for the materials and $799 for labor. No, I'm afraid it's not covered under the warranty, you've voided the warranty by being less than five meters away from the thing."

Respectfully,
Myriad



You know there's no fighting the insidious march of time, and its off-shoot; more monthly bills. You sound sort of cynical. You should play more video games; maybe do illegal drugs...but, hey! I'm not the judge.

[TubbaBlubba]

Can we make giant robots from this stuff already?

[bit_pattern]

Your wrong. Graphene was only isolated in 2004 using scotch tape and tweezers. It was not synthesized. Synthesis only came after we realized that the stuff actually won't self destruct. Before 2004 that scientists weren't even sure if the material would remain stable once you isolated it.

I believe size is actually becoming more of a detriminant than conductivity.

We really shouldn't expect huge speeds at this point. Graphene itself has two main problems. First of all as you point out there is no reliable fabrication technique that doesn't involve scotch tape. Second of all it actually is a horrible semiconductor in its present state. You actually have to dope the thing and to introduce a bandgap. So yeah its possible that we could get huge speeds but we are really in the infancy of working with this material.

Soooo, whay uou are saying is that I should be investing in Scotch Tape shares?

[MattTheTubaGuy]

I wonder how reflective it is. I calculated that it weighs about 0.5kg per square kilometre, so it could be an ideal material for a solar sail, or at least a base to put something more reflective on it.
I do kind of find it funny that the physics Nobel prize went to some people who were effectively playing with pencil leads!:D

[Cuddles]

I wonder how reflective it is. I calculated that it weighs about 0.5kg per square kilometre, so it could be an ideal material for a solar sail, or at least a base to put something more reflective on it.

Reflectivity may not be that much of an issue. A perfectly reflective material only gets double the thrust of a perfectly absorptive one. If it's a choice between a huge sail made of this stuff, or a much smaller reflective one of the same weight, you'd likely be better off going with this. Given how little it weighs, even just a reflective coating may not be worth it for the mass increase.

[ThatSoundAgain]

I do kind of find it funny that the physics Nobel prize went to some people who were effectively playing with pencil leads!:D

Well, it's also a world first in that one of the winners, Andre Geim, is also an Ig Nobel laureate. Which makes this very cool.

[dasmiller]

Reflectivity may not be that much of an issue. A perfectly reflective material only gets double the thrust of a perfectly absorptive one. If it's a choice between a huge sail made of this stuff, or a much smaller reflective one of the same weight, you'd likely be better off going with this. Given how little it weighs, even just a reflective coating may not be worth it for the mass increase.

Solar sails work on both light pressure and solar wind. IIRC (and it's been a while), in our neighborhood, the solar wind is about 2x the photon pressure, and the solar wind doesn't care if your sail is reflective.

OTOH, if you want to use your solar sail for laser-launching interstellar probes, then the solar wind is far less relevant.

[Toke]

Reflectivity may not be that much of an issue. A perfectly reflective material only gets double the thrust of a perfectly absorptive one. If it's a choice between a huge sail made of this stuff, or a much smaller reflective one of the same weight, you'd likely be better off going with this. Given how little it weighs, even just a reflective coating may not be worth it for the mass increase.

I believe it would make a huge difference if you want to tack/cross?

[dasmiller]

I believe it would make a huge difference if you want to tack/cross?

For the photonic part of solar pressure, yes, it would make a huge difference. A perfectly absorbing material could generate only a radial force, whereas a reflective material could generate forces at large angles (of course, the force gets smaller as the angle-from-radial gets larger).

And, again, if you're using your sail for laser-launching rather than relying on solar pressure, then photonic pressure is pretty much all you have to work with.

[MattTheTubaGuy]

Reflectivity may not be that much of an issue. A perfectly reflective material only gets double the thrust of a perfectly absorptive one. If it's a choice between a huge sail made of this stuff, or a much smaller reflective one of the same weight, you'd likely be better off going with this. Given how little it weighs, even just a reflective coating may not be worth it for the mass increase.

true, don't know why , but I completely forgot that!

on the other hand, how transparent is it? with how thin it is, light might just pass straight through it, which wouldn't be very useful.

if it is very transparent, then it would be a good base to put something reflective on it, if it can stick easily. it might be nearly impossible to stick anything on it.