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Quantum Wires
Posted by
CmdrTaco
on Sun Apr 17, 2005 10:20 AM
from the i'll-believe-it-when-they're-conducting-my-mojo dept.
from the i'll-believe-it-when-they're-conducting-my-mojo dept.
Silverlancer writes "Room temperature superconductors have often been a hallmark of far-future science fiction. But fortunately for us, they're here today, according to MIT's Technology Review. Richard Smalley, winner of the 1996 Nobel Prize for the discovery of the buckyball, is currently heading a project to produce a prototype carbon nanotube superconductor. They've already produced some wires up to 100 meters long--the only thing left to do is figure out how to produce only a certain type of nanotube, the "5,5 armchair nanotube," that conducts so well that it can be considered a superconductor."
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Armchair... (Score:5, Funny)
Re:Armchair... (Score:5, Informative)
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Re:Armchair... (Score:5, Funny)
They appear somewhat larger than I expected. Are they being held by nanohands, or is there still a couple of years worth of work ahead trying to miniaturize them?
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Re:Armchair... (Score:5, Funny)
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Superconductors (Score:4, Funny)
That out the way, this is great news. There are so many useful scientific applications for superconducting wires that this is really cool news, once you get over the ethical dilemma caused by the fact that they are making them by *cloning* the orginals. It's ok to clone wires but not people? Hypocrites.
Dr. Smalley talks to the senate (Score:5, Informative)
Power distribution efficiency (Score:4, Funny)
In short, not all new technologies will help bring about the worker paradise. Scientist and their capitalist pig ways!!! Soon the proletariat will rise and all you carbon nanotube superconductor makers will find yourselves up against a brick wall...
*bang!*
Optical Computing versus Quantum Wires (Score:5, Interesting)
So what's the future look like? Quantum processors with superconducting and optical connections? I wonder how these various technologies will actually be deployed?
Re:Optical Computing versus Quantum Wires (Score:5, Funny)
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EMR from high tension power lines? (Score:4, Interesting)
Re:EMR from high tension power lines? (Score:5, Informative)
1. Lower losses in cables, so less power needs to be transmitted
2. Lower resistance means we can pump more power into them. This becomes handy in electromagnetics (example: maglev trains). Less energy is wasted in heat, and less cooling is required.
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Re:EMR from high tension power lines? (Score:5, Informative)
So if you could replace vast swaths of conventional copper electric transmission and distribution lines with superconductors, you could theoretically switch to DC power in these applications, which would have some interesting effects on the rest of the electrical distribution system.
Strict DC voltage on the power lines would virtually eliminate the EM radiation. You would still get some EM when you turned things on or off, or if the amount of power the line carries changed at all, but there would be a HELL of a lot less.
Lower voltages could be used, which would be safer (less chance of electrocuting people), and connectors (plugs, receptacles) designed with lowe voltages in mind would be cheaper to produce and certify.
Also, many devices in the home (especially computer equipment, or anything with circuit logic in it) need to convert the 110V AC current into much lower-voltage DC (2-5V DC, usually) to operate chip logic. This in generally an inefficient process, with a lot of power given up in the transformers and inverters to heat. Granted, you'd have to redesign all the home devices that currently use AC power directly (mostly lights and appliances) to run on DC, it could be done.
Really, the only problem would be the massive costs of switching over from one standard to another. All of those applicances and such would become useless on the new standard, which means everybody has to go out and buy new stuff. If you tried to switch the distribution over to DC in one go, I can see a lot of people having a lot of problems with it. And it wouldn't be practical to change the distribution bit-by-bit, either.
If you just wanted to change the transmission side, and leave the consumer out of it entirely, you'd have to replace a lot of power generation infrastructure. This could be done more slowly, I'd imagine, but it would still be expensive.
But then again, there's nothing that prevents you from continuing to run AC current on superconducting wires. That's probably what will happen, because it's the cheapest option.
I don't see anyone caring too much about interference from power lines in the 60Hz frequency band, anyway--not like we use those frequencies for anything.
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Article Summary: (Score:4, Funny)
In other news, I am now a billionaire with a super model trophy wife. The only thing left is for me to get a lot of money and a hot wife.
really a superconductor? (Score:5, Interesting)
Re:really a superconductor? (Score:5, Insightful)
No. Superconductors must be able to form so-called Cooper Pairs in order for electrons to move in the coherent manner in which no energy is lost. I gather the rules are a little different at really small scales where tunneling becomes a much bigger issue and some of the energy relationships are backwards, but the principle is still the same; if electrons bang into something they lose energy.
Metallic carbon nanotubes, to the best of my knowledge, cannot be made crystalline (perfectly regular) over large enough domains for this to happen thus there is "minimal energy loss" and they are really just very, very, very low resistance conductors (you can tell the difference by looking at the temperature dependance of the resistance).
The thing is, unless you want to build a mag-lev train, you don't really need a perfect super conductor. Right now the conductivities of the metals used in electronis are around 10^6 - 10^10 (inverse ohms per centimeter) and you can put your hand on your computer case to see just how much energy is dissipated as heat. If you increased those conductivities (with metallic carbon nanotubes for example) then your heat sink shrinks and your clock cycles come up... Assuming we can wire teeny tiny circuits with nanotubes. More importantly, you can drive portable electronics with less power, and thus smaller batteries.
BTW (regarding the very first post), some of the Slashdot Armchair Scientists (there are other sciences besides physics too you know) out here in computer land have Masters and PhDs and have published or worked in the field. Some of us have even met and/or worked with the people mentioned in the articles. I wouldn't be so quick to push aside honest criticism, afterall that is what scientists are trained to do - be skeptical :)
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Re:really a superconductor? (Score:5, Informative)
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Investment in superconducting vs. alt. fuel... (Score:5, Interesting)
So much work (and funding) is being poured into finding alternative energy sources, I wonder how much the discovery of a scaleable, inexpensive, widely deployable (as in converting the world's energy grid) superconducting power distribution system has been quantified.
I do understand that this isn't that, and that there are a million barriers to be overcome, and that fossil fuels need a replacement Real Soon Now, but I do wonder if anyone knows of any studies out there trying sort out how much energy is currently lost in the distribution of consumer power, and how much less we'd need to generate if a practical superconducting solution is found.
Factoring in a reasonable probability of success in both sides, it would be interesting to see whether the potential cost/benefit of investments in finding superconducting solutions all the way to the last mile might be as or more efficient in the long run than funding research in new power sources.
I know, it shouldn't be either or in any case, but it's just a thought...
The armchair nanotube... (Score:4, Funny)
So if that electron in your life is giving you heat about the pressure they are under this new product from LazyBoy is the perfect gift for them!
superconductor != 0 resistance (Score:5, Informative)
The most essential thing about a superconductor isn't the zero resistance, but the meissner effect [gsu.edu]. So if they manage to create wires with near-zero resistance, they will not have created `near-superconductors'.
For energy transportation and storage it doesn't matter all that much, cause zero resistance (even without superconductivity) would make energy transportation and storage better
LEDs (Score:5, Interesting)
Even if the carbon nanotubes are not technically superconductors, if their resistance is much lower than copper they might be ideal for low voltage home wiring. You could step the mains down to 5 or 12 volts in a central location in your house, and power the all your low voltage electronics without having to worry about I^2R losses.
The Smalley nanotube effort: the accurate version (Score:5, Informative)
Separately, Smalley and collaborators have been working on spinning fibers from ropes of nanotubes (basically short (less than 1 micron) tubes bundled together by van der waals forces). Those are the fibers that can be meters long. These fibers do not consist of meter-long tubes!
Finally, metallic nanotubes are not room temperature superconductors. In fact, they are not even ballistic over length scales larger than a micron. Smalley's habit of implying otherwise is really annoying to any physicist who knows anything about these systems.
Now, a long fiber of only metallic nanotubes would still have conductivity better than copper at much less the weight, and would therefore be very important industrially if it could be made economically. There is a huge difference between that and having no electrical resistance, though.
Re:wires... (Score:5, Funny)
Sure... Now you just need the girls.
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Nah, Monster Cable will capitalize on it! (Score:5, Funny)
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Re:Dubious Logic (Score:5, Informative)
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Oh! here's an article on nanotube microchips (Score:5, Informative)
From the url:
"Even though such transistors are still in their infancy, says IBM's Avouris, "Carbon nanotubes can get around most of the problems that doom very small silicon devices." In the lab, he has backed this statement up. It took him four years to assemble his current, third-generation prototype of a carbon nanotube transistor, but in the end, the device can carry up to 1,000 times the current of the copper wires used in today's silicon chips, making it vastly more efficient."
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