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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...
Somehow i also doubt the claim "replacement for silicon", silicon is not used in IC-s for its conductivity properties, au contraire, its used because it can be doped to become a N or P semiconductor. Interconnects in IC-s are made with plain old aluminum and copper and interconnects are really not the point where power is consumed. Lion share of power in FET based logic is used charging and discharging transistor gates, that is the losses are capacitive, you can reduce the losses by making smaller transistors but you really cant affect it by material selection.
It is right and proper to have doubts about new announcements like this. That is the basis of science - the idea of "replicate, then trust, but verify" at the core of scientific approaches. If this turns out to be either an error, a late April-fools joke, a scam, a one-off result that cannot be replicated, or a valid result within a small range of constraints, then it will be labelled as such.
However, if subsequent independent experiments show a robust and consistent process that can be replicated easily, then I for one will welcome our new (1 atom-thick) tinfoil hat-wearing overlords...
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
You are wrong.
The evidence against perpetual machines are only for machines with a higher than 100 percent efficiency, not machines that approaches 100 percent efficiency. You can have a wheel in space that spins perpetually, you cannot extract energy from it without slowing it down.
Also, as far as I know the 'proof' is based on a statistical observation of how energy works with a macroscopic number of particles.
While it is highly unlikely that anyone can build an energy creator by working on a subatomic level I don't think that there is any hard evidence that proves this impossible. To get that proof one would probably have to explain why matter and energy exists at all and why it can't happen again.
Usually science in this sort of parers is valid. Just that journalists "translate" it to load of crap and attach applications to the science that were never part of the original paper.
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.
AC, Superconductor. Superconductor, this is AC.
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
"Trust" and "verify" are contradictory. It's fine that you want to verify, but don't pretend that you are trusting while you actively violate the concept of trust.
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
After reading your post, I was quite sure there were no spelling errors. I trusted that there are none, but I verified it to be sure. What's exactly contradictory there?
Since it is not logically possible to be always correct, once in a while something you trust will actually turn out wrong. As this is the case, it is very beneficial to verify things once in a while even if you trust them.
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,
http://arxiv.org/abs/1306.3008 http://arxiv.org/pdf/1306.3008v2
Bzzzt! wrong. If I trust you, I will verify your work. If I don't trust you, I won't even bother to look at it.
Trust is about honesty, not about infallibility.
"Trust but verify" is a Russian proverb popularized by Ronald Reagan.
http://en.wikipedia.org/wiki/Trust,_but_verify
Room temperature superconductor? Really? I doubt somehow.
The article talks about very low power transmissions. At one atom layer thick you could however possibly layer stanene and an appropriate insulator to achieve higher currents. This is in line with what has been observed in the material layering in high-temp superconductors.
They used the Vienna suite for simulation. I have yet to find their experimental observations in the paper.
All rites reversed 2010
the losses are capacitive, you can reduce the losses by making smaller transistors but you really cant affect it by material selection
Yeah, the reason why material selection doesn't matter in capacitors is precisely why many of them are being manufactured using the fairly rare element named tantalum. It's just for the fun of it. ;-) Perhaps you're right about the interconnect material selection but there's a lot of material selection going on in modern ICs beyond that.
Ezekiel 23:20
I suppose "blindly trust" and "verify" are contradictory. Science, and just about all of life, isn't built around blind trust. I trust that people will drive on the right side of the road and stop at red lights, but I watch just to make sure some fool doesn't violate those basic rules. If I didn't trust in those things, driving would be terrifying experience. But if I trusted blindly, I would get into far more accidents than I do.
What a fool believes, he sees, no wise man has the power to reason away.
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,
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.
If you don't really trust anything you haven't personally verified yourself, you can't get very far in real life. Have you verified every line of code that runs on your computer or do you trust it enough to run it anyway? What about the compiler? Do you ever use results from your coworkers without digging through every calculation down to every assumption and verify them? Trust is a measure of confidence in your word, which is weighed against how important it is. If you have no confidence in it, you don't want to waste any time on it (assume false, test false). If you have a bit of confidence that it's might be worthwhile you verify it. (assume false, test true). If you think it's probably right, but you want to verify it that's stronger (assume true, test true). And if you trust it implicitly that's of course trust (assume true, test false).
Live today, because you never know what tomorrow brings
How else, pray tell, are in silica calculations going to be described any other way?
It's a little more than "speculation", but I figure your armchair science degree probably didn't prepare you for that.
In day-to-day life you have to trust almost everything to get anything done, but the GP was talking in particular about trusting new scientific results. Even then if several independent scientists have verified it I can trust it without verifying it myself, but trusting an initial scientific finding that no one else has verified is just foolish, no matter how smart and established the original scientist is. There are different levels and meanings to the word "trust", and as GP pointed out there has to be a certain level of trust for anyone to even bother to try verifying or debunking a result (because there are far too many crackpots out there to deal with them all).
That's something worth posting under a pseudonym. Don't be shy.
All rites reversed 2010