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Physicists Induce Superconductivity In Non-Superconducting Materials (phys.org)
An anonymous reader quotes a report from Phys.Org: Researchers at the University of Houston have reported a new method for inducing superconductivity in non-superconducting materials, demonstrating a concept proposed decades ago but never proven. The technique can also be used to boost the efficiency of known superconducting materials, suggesting a new way to advance the commercial viability of superconductors, said Paul C.W. Chu, chief scientist at the Texas Center for Superconductivity at UH and corresponding author of a paper describing the work, published Oct. 31 in the Proceedings of the National Academy of Sciences. The research, demonstrating a new method to take advantage of assembled interfaces to induce superconductivity in the non-superconducting compound calcium iron arsenide, offers a new approach to finding superconductors that work at higher temperatures. Superconducting materials conduct electric current without resistance, while traditional transmission materials lose as much as 10 percent of energy between the generating source and the end user. That means superconductors could allow utility companies to provide more electricity without increasing the amount of fuel used to generate electricity. To validate the concept, researchers working in ambient pressure exposed the undoped calcium iron arsenide compound to heat -- 350 degrees Centigrade, considered relatively low temperature for this procedure -- in a process known as annealing. The compound formed two distinct phases, with one phase increasingly converted to the other the longer the sample was annealed. Chu said neither of the two phases was superconducting, but researchers were able to detect superconductivity at the point when the two phases coexist. Although the superconducting critical temperature of the sample produced through the process was still relatively low, Chu said the method used to prove the concept offers a new direction in the search for more efficient, less expensive superconducting materials.
There's some change in material that at low temperature some threshold is met that changes the mechanism of conduction to a mechanism that is super efficient. So what is that new configuration? What threshold is met?
Not a physicist by any chance here, but how is this possible? I thought superconductivity was pretty much binary - either you are or you are not.
" -- 350 degrees Centigrade" Well, that's cold !
If it can be used as a superconductor then by definition it is a superconducting material. Just because we didn't know how to do it in a particular material previously is irrelevant.
You haven't reached a superconductive state yet. You are giving to much resistance.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
The material is not superconducting any time other than during phase transition.
I'm not a chemist so I would defer to someone who is but...
As I understand it you are correct but that doesn't make the title make any more sense. Either the material can superconduct or it cannot. All other superconducting materials can only superconduct under specific conditions as well so that's nothing new. The fact that it can only do it during certain phases or phase transitions doesn't change what the material is made of, just how it is structured. Just because something is not entirely solid or not entirely liquid for example doesn't change what it is. To use a stupid simple example H2O is still H2O regardless whether it is ice or liquid water. It only changes to something else when the constituent molecule separate. Perhaps I'm missing something?
It's doubtful whether we could maintain such a lack of state indefinitely.
Would seem to be difficult I agree.
That pretty much makes it not a superconducting material.
Not sure I agree with this. It just is a superconducting material under very specific conditions.
As you say it's hard to know if there is any utility in this finding but it's interesting all the same.
A man with a fascinating history:
http://ethw.org/First-Hand:Discovery_of_Superconductivity_at_93_K_in_YBCO:_The_View_from_Ground_Zero
"Fuel" is a generic term for something that is consumed as a source of energy. So it encompasses rainbows and unicorn farts as well as the horrible biomass and fossil fuels that you deride.
On a related note, when will your enlightened society share the secret of "fuel-less" non-solar nuclear power with the rest of the world's huddled masses?
That's like saying it makes no sense to say that by assembling semiconductors into a transistor they can be made to conduct electricity. By your logic if they conduct electricity under any circumstances they must be conductors.
It's nothing like that at all because the very term semiconductor clarifies the matter. Semiconductors DO conduct electricity. Just relatively poorly compared with traditional conductors and better than insulators. We've figured out some clever ways to control and selectively enhance their conductivity under certain conditions much like we have found ways to create superconductivity under certain conditions. The taxonomy here is well understood and defined. We don't call things "conductors in non-conducting materials" because that statement is self contradicting and challenging to parse. As an example the title could have read "Method found to induce superconductivity in new materials" and then you clarify in the article header how it actually works.
This is not how humans use language.
It is when they want to actually be understood.
Even solar power uses fuel, it's just that the fuel supply is located a bit away from us. (About 8 minutes at lightspeed.)
I think we've pushed this "anyone can grow up to be president" thing too far.
...researchers working in ambient pressure exposed the undoped calcium iron arsenide compound to heat...
As opposed to the researchers working in a vacuum, who mostly just died horrible deaths.