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Single-Atom Layer of Tin May Be a New Wonder Conductor
At Kurzweil AI, an article proclaims that the next wonder material for computer chips may be an unexpectedly common one:
"Move over, graphene. 'Stanene' — a single layer of tin atoms — could be the world’s first material to conduct electricity with 100 percent efficiency at the temperatures that computer chips operate, according to a team of theoretical physicists led by researchers from the U.S. Department of Energy’s (DOE) SLAC National Accelerator Laboratory and Stanford University." (Original paper is available here, but paywalled.)
Seems unlikely. Something about complimentary midday meals...
Room temperature superconductor? Really? I doubt somehow. Even if true it cant handle much current, superconductivity breaks under powerful magnetic fields larger currents create.
I note they are being very careful to avoid using the word "superconductor", even though they say you can get 100% efficiency as a conductor. Presumably this is because it isn't inducing electrons to pair up.
Anybody know whether this really is 100%, or just ninty nine point lots of nines percent?
There is no such thing as conducting electricity at 100 percent efficiency. Think about it... it implies perpetual machines, and I believe there's some evidence against the possibility of such a thing :D
so tinfoil, then?
not 100% (nothing really is) but it still works even with holes in it almost no leaking how advanced we are
free the innocent stem cells end health care held hostage in our time
I suppose as small as the connections would need to be that tin whiskers would no longer be an issue!
At least as far as I can tell without access to the paywalled concept.
Important questions would be:
What is the maximum current that can be transported through strips of various widths?
How sensitive to defects is the process?
Tin is going to be a major problem for much semiconductor processing - as it means you basically now can't solder the chip, or do any even 'low' temperature processing after it's deposited - it has to be the last layer.
Arxiv to the rescue: http://arxiv.org/abs/1306.3008 (This may lack editorial changes etc. made by the journal, but should be factually complete.)
Stefan Axelsson
NOW they tell me my tinfoil hat in fact amplifies my brainwaves to be read. THANKS A LOT LONE GUNMEN!
Science advances one funeral at a time- Max Planck
No. Superconductors of any critical temperature don't imply infinite power storage. They need to be cooled more and more as they are subjected to larger and larger magnetic fields (generated by the circulating current that they contain). The nominal critical temperature is for when they store zero current. Even if you could keep a superconductor at exactly zero degrees, it would still only store a finite amount of energy.
Anyway, this isn't about superconductors; its a totally different phenomena called the quantum hall effect. This has been around since the 80s; they're just claiming to have found a material that (according to their models) has a large regime of zero-resistance operation. The problem with using the QHO for practical purposes is that it requires a crazily strong external magnetic field (~1T).
For those of you not in the semiconductor business, the fact that these conductive strips is pretty important too. Most of the capacitance (that has to be charged and discharged whenever a node switches, causing losses in the transistors driving the node) is sidewall capacitance: capacitance between adjacent lines on the same level. Single-layer conductors won't completely do away with lateral capacitance (fringing, for instance) and the vertical capacitance will still be there -- but there's going to be a big reduction in power if they can get this to work. My guess is that by the time it reaches production it won't exactly be one layer, either -- it'll be a laminate with multiple redundant layers.
Always assuming the predictions play out.
Lacking <sarcasm> tags,
One Tin Solder walks away!
http://arxiv.org/abs/1306.3008 http://arxiv.org/pdf/1306.3008v2
So it can conduct small current with little or no resistance
and its not scaalable
good for chips, but you're not going to be transporting gigwatts or power from the wind farms to the cities with no losses, or improving the efficiency of your electric car.
For someone who is not an expert in the field, what is the efficiency of the conductor? It seems to refer to the fact that no charge is lost (dissipated) between the ends of the conductor, but it's not clear.
I assume since no one used the word "superconductor" that it has a finite resistance; does anyone know what the resistance is? (would large bundles of these conductors be useful for energy transport?)
They will have to deal with Tin's tendency to slowly grow whiskers of metal (and the resulting short circuits). Reference:
http://en.wikipedia.org/wiki/Whisker_(metallurgy).
Whiskering is a phenomenon of crystalline metals under strain. This stuff isn't crystalline, and it's not really metallic in the usual sense. Fullerenes are strange things indeed, but if tin atoms are wandering around then the stuff would be too unstable to use for most things anyway.
Lacking <sarcasm> tags,
"...according to a team of theoretical physicists..."
Ok.
How much electricity and how far to seperate layers (to make sufficient sized 3D conductor for some sufficient amount of electricity to be carried)
100%'efficiency' doesnt mean its any large amount (voltage or current)
Those are the practical matters, as well as handling something one atom thick in an industrial process.
Right, the usual fundme bullshit wrapped as article. Come back when you have something beyond speculation.
These guys are talking about a 2D topological insulator. This is the current hot area of research in condensed matter physics, and is absolutely not a superconductor.
A topological insulator is best described as an insulator, which for very particular types of conduction (direction, location and energy limited) acts like a very good metal. It's really interesting, and scientists are trying to show it will have practical use, and these materials might end up in a computer chip in a few years, but...
There is a big difference between a lab effect and the real world. Carbon nanotubes have most of the same "non scattering" effects you'd hope to find in a topological insulator. Yet, in most actual devices, they do not conduct in bulk the way theory would suggest. For nanoscale systems (these are nanoscale systems) the environment around the material is nearly as important as the material itself, and scattering from the environment (oxides, metals, air) drastically reduces the performance of the material. There are ways around that, but the additional costs and engineering difficulty are generally enough to prevent any practical commercialization.
Organ pipes are made from a mixture of lead, tin and zinc (at least those that aren't made from wood). They last for centuries vs electronics. Many congregations can no longer afford to maintain their old pipe organs, or they no longer use traditional music in their service and rip them out in order to make room for the band. In some cases an effort is made to find the organ a good home but often, tragically, the pipes are chopped up for scrap metal. If this drives up the price of tin, I could see it causing more destruction of existing pipe organs, and putting the price of new construction out of the reach of congregations.
Here's a pdf of the full article:
http://www.scribd.com/doc/186970759/Xu-Y-Binghai-Y-Hai-Hun-Z-Jing-W-Gang-X-Peizhe-T-Wenhui-D-Shou-Cheng-Z-2013-Large-Gap-Quantum-Spin-Hall-Insulators-in-Tin-Fi?secret_password=1s8nqw1pazkc9kw6m3i7
Those wearing hats made of tin foil were always on the money, after all.
Really, that's what we had to drag our butts through interstellar space for? Unobtanium is just tin?
"I have never let my schooling interfere with my education." - Mark Twain
For those interested in a more in-depth treatment... http://arxiv.org/pdf/1306.3008.pdf
It's even worse than that. Tin whiskers - it's a characteristic of the metal. No one knows why, the only suspicion we have is Tin does it to relieve stress in the crystal.
Fullerenes aren't crystals, though. For the same reason that graphene and nanotubes don't have carbon wandering around all over the place, neither is tin likely to. In fact, given the higher mass of a tin atom compared to carbon, it could be a whole lot harder to get one to leave its place in the array.
Lacking <sarcasm> tags,
if(!strcmp(string, "100 percent efficiency")) {
printf("Bullshit!\n");
}
but scientists are now hard at work to develop larger tin atoms.
It's supposed to be completely automatic, but actually you have to press this button.