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A pellet of yttrium barium cuprate, when exposed to a styrofoam cup filled with liquid nitrogen, superconducts and levitates a neodymium magnet. Scientists have finally figured out how these superconductors and others work, a mystery that has long eluded them.  (Source: coronene.com)
With a newfound technical understanding, the skies are clear to develop truly super superconductors

There has been a number of advances in the field of superconducting recently.  Superconductors, materials that conduct electricity with no resistance below a certain temperature (the critical temperature, Tc), have a variety of incredible applications.  For example, superconductors could offer electricity transmission with no losses from power plants, saving the country's money and fuel, could power faster computers, and could make ultra-efficient motors.

Over the last few years, many breakthroughs in the field of conductivity have been achieved.  The first superinsulators have been created and magnetism-immune superconductors have also been made.  The greatest goal of superconductor research -- to achieve room temperature superconductivity -- still remains unattained, but thanks to new cuprate (copper and oxygen) superconductors we're a lot closer.

However, one critical problem was that superconductor behavior in these cuprate superconductors were not well understood -- until now.  Researchers at U.S. Department of Energy's Brookhaven National Laboratory along with partners from Cornell University, Tokyo University, the University of California, Berkeley, and the University of Colorado have finally developed a cohesive explanation for superconductor behavior.

To gain their insight, the researchers used "quasiparticle interference imaging" with a scanning tunneling microscope to look at Cooper pairs of electrons.  Cooper pairs are paired electrons in superconductors that allow for the phenomena to occur.

The puzzling phenomena, which the scientists solved, was that in normal superconductors raising the binding energy, to hold these pairs together raises the critical temperature closer to room temperature.  However, in cuprate superconductors, which have higher starting temperatures, raising the binding energy actually lowers the Tc, the opposite of the desired result.

Researchers determined that this is due to a "quantum traffic jam" effect.  Normally cuprates are stuck in a jammed stated known as the Mott insulating state, named after the late Sir Neville Mott of Cambridge, UK.  To create cuprate superconductors, electrons are removed from cuprates, leaving holes.  Cooper pairs can then start to flow into these holes, allowing for superconduction, akin to a couple cars exiting the highway during rush hour starting traffic moving.

However, the critical discovery the researchers made was that increasing the binding energy also increased the "Mottness" of cuprate superconductors.  Thus, raising the temperature only made the traffic jam worse, lowering the critical temperature.  Seamus Davis of Brookhaven National Laboratory and Cornell University, lead author on the paper describes, "It has been a frustrating and embarrassing problem to explain why this is the case."

Now the dilemma becomes applying this new knowledge to new superconductors.  Traditional superconductors have low Mottness, allowing for binding energies to be used to raise their critical temperature.  However, they start at very low critical temperatures, so the temperature can only be raised so high, typically well below the starting critical temperatures of cuprate superconductors.  Cuprate superconductors start high, but can't get any lower.

A new hope is that superconductors comprised of arsenic and iron, instead of copper and oxygen, might have less Mottness, but be able to make gains from raising binding energies, but also enjoy higher starting temperatures.  Mr. Davis states, "We need to look for materials with such strong pairing but which don't exhibit this Mottness or 'quantum traffic-jam' effect.  Our hope is that (iron/arsenic superconductors) will have less 'traffic-jam' effect while having stronger electron pairing."

If such a superconductor can be created and tuned, room temperature superconductivity may finally be achieved, and affordable, bringing great economic and scientific gains.  For now, the breakthrough represents perhaps the greatest advance in understanding superconductivity yet.





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More great news for the circuit world!
By DeepBlue1975 on 8/29/2008 8:53:20 AM , Rating: 3
I wouldn't think this could be so affordable at first when they figure out how to produce actual working chips out of superconductors, but surely they will be affordable enough to start on the highest end market for very specific applications (I'd think that the military and scientific community will be the first to have these) and then start to climb down onto the market.

With superconductor findings in progress, an everyday growing wealth coming from optical computing research, and the imminent coming of SSD technology to desktops, I start to feel really excited about the next 1 or 2 decades to come, I'm sure it'll be a fantastic time for the computing industry, maybe as exciting or more than the time when the first superscalar chips and 3d processing cards started appearing on the PC market.

Things have definitely been very boring for the past years in the industry (same technology everywhere, even Macs turned to normal PC hardware, and we've been seeing only innovation without great applied breakthroughs for no less than 10 years...), now the paving of a new paradigm in computers starts to slowly show itself on the far horizon.

Seems I'll start being very busy devouring all the information I can on these advancements :D




RE: More great news for the circuit world!
By carroll on 8/29/2008 9:28:40 AM , Rating: 3
Whats most interesting to me would be the ability to store (electric) energy with great efficiency.

I've seen a superconductive ring being 'injected' with current and after removing the voltage, that current would just keep circling that ring with negligible decrease in strength - i think that was for a period of a day or more when they tried it.

Now if room-temperature superconductivity was achieved someday and the cost in terms of energy to maintain that state is not too high (or none even, i don't know if they would actually need something to keep the state), then this would be a great thing, next to zero-resistance power lines.


RE: More great news for the circuit world!
By svenkesd on 8/29/2008 11:07:34 AM , Rating: 2
I believe a superconductive ring is the closest possible working (man-made) example of perpetual motion.

http://www.allaboutcircuits.com/vol_1/chpt_12/7.ht...


RE: More great news for the circuit world!
By masher2 (blog) on 8/29/2008 2:26:44 PM , Rating: 3
Interesting, but that site is in error. Perpetual motion is indeed barred by the laws of thermodynamics. What the author of that site is referring to is the 1st Law, which boils down to "you can't win" (on generating energy perpetually).

However, there is also the 2nd Law, which boils down to "you can't break even". Entropy always increases. Even a superconducting ring will eventually stop moving...though it can take many, many years.


RE: More great news for the circuit world!
By InsaneGain on 8/29/2008 4:12:51 PM , Rating: 2
Assuming the ring does in fact have zero resistance, where would the energy in the current go if it inevitably slows down?


RE: More great news for the circuit world!
By masher2 (blog) on 8/29/2008 4:35:12 PM , Rating: 3
The same place it does in a normal conductor -- through eddy currents / resistive heating. It simply happens at a rate many orders of magnitude lower, due to the resistance being so close to zero.

Mind you, I'm not saying this is what happens. Most people will claim the classical laws of thermodynamics don't apply to a quantum effect like superconductivity. A few will say they do, and superconductivity may be "super", but it's not "perfect". I'm just pointing out that there *is* a conflict between the two.


By carroll on 8/29/2008 4:49:15 PM , Rating: 2
still, i can't get it into my head that a current would flow without a difference in voltage/potential 'driving' it. :O

where's the electric field that i learned pushes the electrons (or sucks - heh i always hated that technical versus scientific awkwardness of electric current)?

guess i'll have to imagine it like a solid object being accelerated to some velocity and then moving on and on with zero friction.


RE: More great news for the circuit world!
By kayronjm on 8/29/2008 7:09:35 PM , Rating: 2
Exactly, the key point to note is that resistance cannot be zero due to the nature of what resistance really is, it would be physically impossible for it to be zero. It is merely extremely close to zero, at least in orders of magnitude compared to a normal conductor.


By foolsgambit11 on 8/30/2008 2:28:27 PM , Rating: 3
Woah, woah woah. Woah. Slow down there. Superconductors are, in fact, zero resistance conductors. Zero. Zilch. None. That's their definition. A current would, theoretically, continue to travel in the closed loop forever. In practice, this doesn't happen because superconductors have temperature requirements, or in the case of high-temperature superconductors, are sensitive to nearby electromagnetic fields, which will cause resistance.

Superconductivity is a quantum effect manifested on a macro scale, but it is only visible under rather stringent circumstances. Maintaining those circumstances currently takes energy input (ergo not violating the laws of thermodynamics).

What scientists are essentially looking for by advancing superconductivity research is an 'exception' to the laws of thermodynamics. Remember, they are only called laws because we haven't been able to find a case where they're wrong. This could be a case. Or, the laws of thermodynamics could indeed hold true in all circumstances, and room temperature superconductors could be an impossibility.


RE: More great news for the circuit world!
By emboss on 8/30/2008 8:10:10 AM , Rating: 5
quote:
Perpetual motion is indeed barred by the laws of thermodynamics.


Err, nope. There's nothing from a thermodynamic law point of view that requires an isolated spinning top (in a perfect vaccuum, in zero gravity, in a mu-metal case, etc etc) to stop spinning. What the laws do disallow is perpetual motion where work is being done.

quote:
Even a superconducting ring will eventually stop moving...though it can take many, many years.


Incorrect. In a steady-state situation (ie: not injecting or withdrawing current) a conventional superconductor has *exactly* zero resistance, and the current in a superconducting ring will remain constant. Given, of course, that both the current and magnetic field are below the critical values. Experimentally, people have watched loops for years and been unable to measure any change in the current.

Type II superconductors suffer flux creep at sufficiently high currents and temperatures, but the limit is always being pushed up through developments in flux pinning.

Also, this doesn't violate any law of thermodynamics since, again, no work is being done. What would violate the second law would be if you could inject current into a loop, and later draw it out with 100% efficiency. This is not the case, since the resistivity of a superconductor to AC currents is non-zero.

Finally, the traditional expression of the second law (only entropy-increasing processes are permitted) breaks down in some quantum-mechanically driven processes. This has even been experimentally demonstrated. However, the applicability of these violations has been a long-running topic for debate, since many parts of thermodynamics don't make a lot of sense when you're talking about single entities.


RE: More great news for the circuit world!
By masher2 (blog) on 8/30/2008 10:51:49 PM , Rating: 2
> "What the laws do disallow is perpetual motion where work is being done."

No. Precisely, the Second Law states that the thermodynamic free energy of any system will tend to decrease. It doesn't presuppose that work is being done. An ice cube melting in a cup is a system of increasing entropy, one that is therefore losing its ability to do work -- even though no work is being done.

> "There's nothing from a thermodynamic law point of view that requires an isolated spinning top. . .to stop spinning"

Sure there is. Google "heat death of the universe" for a rationale why.

> " Experimentally, people have watched loops for years and been unable to measure any change in the current"

The decay constant of a superoconducting ring is enormous -- but not infinite. Experiment has set a lower bound of some 10^5 years on such a ring; theory sets an upper bound of ~ 10^10^10. Very large, indeed, but still finite.


By emboss on 9/1/2008 5:14:23 PM , Rating: 3
quote:
No. Precisely, the Second Law states that the thermodynamic free energy of any system will tend to decrease. It doesn't presuppose that work is being done.


First, your definition of the second law is a bit sloppy, since it requires the thermodynamic free energy to be defined (which can be difficult in non-equilibrium systems). A more rigorous expression is that an irreversible process in an isolated system will cause the entropy of that system to increase. Second, do you or do you not agree: "What the laws do disallow is perpetual motion where work is being done."? Note that nowhere do I state that this is ALL the laws disallow.

quote:
"There's nothing from a thermodynamic law point of view that requires an isolated spinning top. . .to stop spinning"

Sure there is. Google "heat death of the universe" for a rationale why.


What process would result in the top slowing down? Keeping in mind that this is our perfectly isolated system, and angular momentum must be conserved. A simpler situation (to avoid the whole atomic angular momentum thing) would be a mass moving linearly - again, there is no process that will result in the mass slowing down. This is trivial to see by considering that linear momentum must be conserved. The root cause of this perpetual motion is that the system as described is already in the highest-entropy state that can be obtained through the available processes.

quote:
theory sets an upper bound of ~ 10^10^10.


Cite? I am aware of no such bound for conventional (type I) superconductors, besides the universal limits imposed by things like a big crunch. But that really can't be boiled into the decay constant - it's more a breakdown in the isolation of the system :) A Cooper pair cannot lose energy through interaction with the superconductor any more than an electron orbiting a nucleus can lose energy by interacting with the nucleus (electron capture notwithstanding). Type II superconductors still aren't well understood, so I wouldn't be surprised if someone somewhere has managed to develop a theory that gives an upper bound for the decay time.


RE: More great news for the circuit world!
By menace on 8/29/2008 4:51:00 PM , Rating: 2
"I believe a superconductive ring is the closest possible working (man-made) example of perpetual motion."

What about a satellite in geosync orbit? It can stay in orbit for decades or more. I think they plan to put spacecraft into Lagrange points, which will stay practically forever in orbit, unless knocked out by a rogue object.


RE: More great news for the circuit world!
By Suntan on 9/4/2008 2:33:10 PM , Rating: 2
quote:
What about a satellite in geosync orbit?


That’s like saying that a rock, sitting on the floor after being dropped, is a perpetual motion machine because it doesn’t fall any farther.

Further, this talk about trapping energy in a superconducting ring of sorts (not going to delve too far into the argument, as I haven’t read what it is really about) is like saying that water, once pumped up into a water tower and held there, is a perpetual motion machine because it contains potential energy that isn’t diminishing over time. That’s not what a perpetual motion machine is, and not what the laws of thermodynamics are talking about.

-Suntan


By carroll on 9/5/2008 2:46:09 AM , Rating: 2
i didn't bring up the argument of perpetual motion machines, which indeed doesn't have anything to do here ;)

somehow i don't think that applicaple superconductivity at roomtemerature can that easily be achieved. if it will be, than that'd be wonderful, if it won't than the phenomenon will remain used only in certain circumstances (think LHC for instance ... cost ain't very important there it seems).


By someguy743 on 8/30/2008 12:43:11 PM , Rating: 2
No doubt about it, if the scientists can come up with affordable room temperature superconductor technology it would be a MONSTER breakthrough ... as big as the invention of the light bulb and electricity itself. It would turn the whole energy industry upside down. Electricity would get RADICALLY cheaper. We'd surely be saying bye, bye to the internal combustion engine and liquid fuels in cars. We'd all be driving quick charging pure electric cars with plenty of range. A LOT of electronic products on the planet would get much more efficient and cheaper.

Now if only we could have a MONSTER breakthrough in fusion energy. Then, we might be getting closer to utopia. Unlimited energy that can be transported easily across the world with very little losses.

Til then, we could use room temperature superconducting transmission lines coming from solar thermal and photovoltaic plants in the deserts of the world to transport our electricity around as easily as information is transported over the internet. Same thing with wind farms and geothermal. We could have huge solar farms and huge wind farms located at THE most optimal locations and transport that juice all over the world.


The public is unaware
By jemix on 8/29/2008 8:52:11 AM , Rating: 2
When most people think of superconductivity, they think about cool little things levitating about an inch in the air. They don't fully understand what it's all about. When we finally are able to get a superconductor to work at room temperature, it will be a great day!




RE: The public is unaware
By spuddyt on 8/29/08, Rating: -1
RE: The public is unaware
By Yeco on 8/29/08, Rating: 0
RE: The public is unaware
By ZmaxDP on 8/29/2008 2:25:51 PM , Rating: 5
Yet another clever jibe ruined by poor English...


RE: The public is unaware
By idconstruct on 8/30/2008 12:58:25 AM , Rating: 1
+1


RE: The public is unaware
By sld on 8/30/2008 7:22:44 AM , Rating: 2
+2


RE: The public is unaware
By jemix on 8/29/2008 9:28:37 PM , Rating: 2
Saying "If" is correct, but I'll stick with what I said. I prefer to keep a positive attitude.


Possibly
By luseferous on 8/29/2008 12:25:00 PM , Rating: 5
Interesting article though the breakthrough may only lead to the understanding that room temperature superconductivity wont be feasible.

Just to be clear I'm not nay saying but my take is that this only gives an understanding of a particular hurdle, the hurdle hasn't been jumped yet. It may be that there is not a combination of elements that achieves the desired results. Hopefully there is as it would truly change the world.




RE: Possibly
By Adonlude on 9/2/2008 8:56:12 PM , Rating: 2
Room temperature superconductors would be really nice to have and I am happy that these guys are working towards them but people should realize that there is no reason why "room temperature" superconductivity should necessarily be possible. They could exist but there is no reason to assume they do.

"Room temperature" is a temperature related to an average comfortable temperature that humans are used to experiencing on this planet. This temperature has no relation to the rest of the universe and is seemingly a random lucky phenomenon that we humans find ourselves subject to.

We have no reason to expect the physics of the rest of the universe to accommodate us in this matter.


RE: Possibly
By Suntan on 9/4/2008 2:50:12 PM , Rating: 2
“Room Temperature” is just a dumbed down way of saying ambient temperature. What are really needed are superconductors that can work up to and above 100°F. For days when everyone wants to run their AC and the transmission lines need to carry the load.

Also, people don’t want the traces in their computers (personal or supercomputer) to suddenly lose their superconducting properties and burn up all the traces because the temp got up over 72°F in the room.

No, they say “room temperature” because it makes it easy for the lay people to put more into perspective compared to temps of -200°F and such.

The reason for wanting operation at these temps is because these are the operating temps where they graduate from being more than just university playthings and actually become useful to society.

quote:
We have no reason to expect the physics of the rest of the universe to accommodate us in this matter.


100 years ago, we had no reason to expect the physics of the rest of the universe to accommodate us in the development of spandex either, but Mother Nature blessed us with that miracle.

-Suntan


Are we closer?
By kontorotsui on 8/29/2008 3:08:55 PM , Rating: 2
Do we finally get those backpack-sized unlicensed nuclear accelerators?




RE: Are we closer?
By foolsgambit11 on 8/30/2008 2:39:21 PM , Rating: 2
Yeah, well, let's get ready.

Switch me on...


RE: Are we closer?
By JKflipflop98 on 9/3/2008 3:33:24 PM , Rating: 2
Whatever you do, don't cross the streams.


RE: Are we closer?
By rdevalco on 9/3/2008 3:51:34 PM , Rating: 2
YOU HAVE TO CROSS THE STREAMS TO DEFEAT THE STA-PUF MARSHMALLOW MAN


By phazers on 8/29/2008 2:07:17 PM , Rating: 5
Obviously the fastest and cheapest way to achieve room temperature superconductivity is --- just lower your thermostat! :)

Al Gore would have been proud of this post if he could have but read it already...




Traffic jam theory
By japlha on 8/29/2008 10:31:58 AM , Rating: 2
I though traffic jams only caused problems for the macroscopic world.




RE: Traffic jam theory
By Cullinaire on 8/29/2008 12:22:47 PM , Rating: 2
And you'd be correct in your original thinking.
Those subatomic particles care not whether we get superconduction or not.
Maybe being able to practically apply superconduction might help solve it.


errata
By menace on 8/29/2008 4:13:48 PM , Rating: 2
"Cuprate superconductors start high, but can't get any lower." This should say "higher."

This brings it in line with the previous statement: "However, the critical discovery the researchers made was that increasing the binding energy also increased the "Mottness" of cuprate superconductors. Thus, raising the temperature only made the traffic jam worse, lowering the critical temperature."




RE: errata
By Terberculosis on 8/30/2008 9:17:02 PM , Rating: 2
I think what Paragraph 7 should actually say is

"However, the critical discovery the researchers made was that increasing the binding energy also increased the "Mottness" of cuprate superconductors. Thus, raising the binding energy only made the traffic jam worse, lowering the critical temperature."

We do not yet know if Cuprate superconductors are incapable of attaining higher critical temperatures, and I do not believe that the maximum critical temperature for Cuprates was the topic of this research.


The real question...
By goku on 8/30/2008 2:02:24 AM , Rating: 2
Why are these scientists so convinced that a room temperature super conductor is possible? I know it's a nice goal, but couldn't it be very well an unobtainable one? Why are they so convinced that it's possible to achieve a room temperature super conductor anyhow?




RE: The real question...
By Suntan on 9/4/2008 2:36:34 PM , Rating: 2
Why was that goofball convinced that the earth was round? I mean, it was a nice goal, but it just might be that the world is flat…

-Suntan


...
By DASQ on 8/29/2008 10:29:08 AM , Rating: 2
I think I've seen the same line about 4 times on this site in the last year:
'X breakthrough clears the path for commercial superconductors!'
'Y team uncovers the superconductor room temperature secret, tracks laid for superconductor future!'
'I'm running out of examples here, so let's just assume superconductors and their secrets have been found by some team!'




By KingofL337 on 8/29/2008 11:16:21 AM , Rating: 2
The next 20 years will be interesting indeed.




>><<
By shin0bi272 on 8/29/2008 2:55:27 PM , Rating: 2
Have they looked at lithium titanate? Its made great leaps for lithium ion batteries it could be a good superconductor




Michio Kaku is pleased
By marsbound2024 on 8/29/2008 4:18:58 PM , Rating: 2
I am sure now he'll appear on the Science Channel or Discovery Channel for a revised version of one of his shows about the future.




Correction
By AnnihilatorX on 8/30/2008 11:06:27 AM , Rating: 2
quote:
Cuprate superconductors start high, but can't get any lower.


I think you mean "can't get any higher"




Perpetual Motion
By Risforrocket on 8/30/2008 11:57:11 AM , Rating: 2
Regarding perpetual motion or any such mechanism or concept, you must keep in mind such laws denying that require a closed system. There is nowhere in the 4-space we (don't) live in where there is a closed system. Therefore, expect the truth to break your concepts of perpetual motion.

I'm so glad the truth always gets through eventually.




fusion
By obiwankenobi on 8/31/2008 3:12:15 PM , Rating: 2
if this problem will be solve, then i think this will have a big implication for the research of fusion reactors




Styrofoam!
By initialised on 8/31/2008 7:49:59 PM , Rating: 2
an essential part of any semiconductor physicists tool kit!




By DanoruX on 8/29/2008 1:20:17 PM , Rating: 2
The problem is that the cost of running phase change cooling in your computer would probably exceed any benefit you would get from superconductor overclocking, unless it means you can increase performance by orders of magnitude...


By 306maxi on 8/29/2008 1:58:41 PM , Rating: 3
Why are you advertising your cruddy site in posts on dailytech?


By Divineburner on 8/29/2008 11:11:21 PM , Rating: 3
quote:
what about 0 Farenheit

That is a high temperature, a high temperature indeed!


By Titanius on 8/30/2008 5:12:25 PM , Rating: 2
Pfft, 0 Celsius is higher than that.

LOL.


...
By drebo on 8/29/08, Rating: -1
RE: ...
By Icelight on 8/29/2008 11:53:27 AM , Rating: 2
But then the title wouldn't be sensational!!


RE: ...
By luseferous on 8/29/2008 12:08:39 PM , Rating: 2
quote:
Quote
The greatest goal of superconductor research -- to achieve room temperature superconductivity -- still remains unattained

Scientists Solve Greatest Superconductor Puzzle Yet on the road to their ultimate goal: achieving room temperature superconductivity.

There you go fixed. Not quite as snappy tho :)


RE: ...
By JustTom on 8/29/2008 12:49:56 PM , Rating: 2
The title says qualifiers it with yet.


"Intel is investing heavily (think gazillions of dollars and bazillions of engineering man hours) in resources to create an Intel host controllers spec in order to speed time to market of the USB 3.0 technology." -- Intel blogger Nick Knupffer













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