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http://www.superconductors.org/216C209C.htm. This stuff doesn't even have to be under pressure. Alas, it's neither stable nor macroscopic.

There's an alloy known as "Electrum". It's been around since the time of the Pharaohs and was used to decorate the capstones of pyramids as well as to make coins. It's a mix of gold, silver and copper.

But on the periodic table, none of those elements are superconducting. That's due to those elements only have one free electron in the outer shell and two electrons are required to form a Cooper pair.

http://www.superconductors.org...

Jeebus this was covered in Popular Science in the late 80s. The F?

http://www.superconductors.org...

Best reference I could find. I recall the article even covered people playing with styro-foam as a super-conductor.

http://www.superconductors.org...

Up to 53c last report here: http://www.superconductors.org/News.htm

Most people think of superconductors as merely a "perfectly efficient" conductor. While this is true, it just scratches the surface of what's possible with superconductors. Using superconductors just to improve efficiency wouldn't be that big a deal by itself. It would improve battery life a little bit, and maybe drop bulk electricity transmission overheads, but not by much, and certainly not immediately. Making most superconductors into high-tensile wire is a non-trivial exercise, even if cooling isn't a problem -- and it will be! Just because a material is discovered that can conduct at "room" temperature isn't helpful for wire outdoors in direct sunlight, or in a hot environment inside high-temperature machinery. Last but not least, superconductors have current and magnetic field limits that increase as they are cooled past the transition temperature. A superconductor with a transition temperature of 26C would probably have only a few limited applications above 20C.

The other uses are more interesting, and often more amenable to thermal control:

The Meissner_effect provides magnetic shielding, which is useful for all sorts of things, like amplifiers, or for protecting sensitive electronics. This is also what causes magnets to levitate above Type 2 superconductors. I assume that a room-temperature superconductor would be Type 2, so levitation would likely be possible.

The London moment could be used in gyroscopes and the like.

Josephson junctions provide all sorts of functions, like ultra-sensitive magnetic field sensors (think hard-drives and MRIs).

Still, all of that is a bit... meh. I mean sure, you get less noise in your now ultra-sensitive amplifier, and electricity will cost 10% less than it would have otherwise in 30 years. Is this life changing? Probably not really.

A much more interesting potential application than all of those combined is Rapid Single Flux Quantum digital circuitry. That stuff makes silicon look like vacuum tubes. Think 100GHz+, self-clocking, 1000x as efficient as CMOS, and manufacturable now, with only the cooling requirement the big down-side. If RSFQ could be made to work at room-temperature (or even near it), you could be looking at a sudden massive leap forward in computer power like never before. For example, with a power draw 1000x lower, it would be possible to stack every chip in a typical computer into a little "cube", with much shorter wire lengths, and hence, latencies. We can't do this now, because that cube would literally melt in seconds form the heat.

The reality-check of all this is that many MRI machines are still cooled by liquid helium, even though superconductors that work at liquid nitrogen temperatures have been available for a while. This tells you a lot about the limitations that might restrict the application of even a hypothetical room-temperature superconductor. For example, ultra-sensitive sensors and RSFQ may not work at all, because the tiny signal quanta may be swamped by the background thermal noise. Similarly, manufacturability of wire and maximum magnetic field strength is a key requirement for a lot of applications, like MRIs and electric motors.

Personally, I suspect that the first room-temperature superconductor will be initially manufacturable in bulk only as a thin-film, so expect the first decade or two to be mostly about improved circuitry and sensors more than anything else. This might be closer than people think. For example, there's a harmless quack who claims to have achieved superconductivity at 28C by manufacturing extremely complex copper-based crystals as a thin layer between two different traditional copper-based superconductors. Assuming for a second that he's onto something, it gives you an idea

Well, the weird thing is that most of the info on superconductors.org is actually pretty good... Eck's History of Superconductors page is actually pretty good, and he even acknowledges the 138 K ambient-pressure cuprate semiconductor as the current high-Tc record. :-)

Does he say anything about the facilities he has to do this materials synthesis and measurements???

I'm nothing related to this field, but my google-fu is strong today.

This article (bottom of page) explains the 4-number notation to represent numbers of insulating, spacing, separating, and conducting layers. It even has a picture.

No, I have no idea what that means. I can guess at what the fourth number means, though...

A confirmation of one of his earlier materials - a YBCO variant by what appears as legit university scientists.

Well, he does seem to have discovered Weather Underground's logo.

According to this page http://superconductors.org/185k_pat.htm the previous record was actually 185K and it points out the the coldest recorded temperature on the planet is 183.95K. What is actually more exciting (to me at least) is the new non-cuprate superconductors. They are fluorine doped RFeOAs (R = rare earth) with Tc ~ 40-50K. This will hopefully give insight into the mechanisms of non-BCS superconductivity.

Superconductivity was not discovered by IBM, and it also occurred much earlier than 1987. The BCS theory of superconductivity came out in 1957, and the phenomenon itself was first seen in mercury by Onnes in 1911. And while high-Tc superconducters were first seen at IBM, this occurred in 1986.

The problem with liquid helium (This made MRI scanners horribly impractical for a LOT of years) is that it has 1/20 the heat capacity of nitrogen, and you have to suck a thousand times the power to get down to helium temperatures compared to nitrogen. There would also be no quantum anomalies with silicon. It can only be compelled to a superconductive state under Extreme pressure.

BTW, which is it... are we mounting it in a vaccuum or under liquid helium :)

I wrote a paper on Type I superconductivity (appears in metals when cooled to a few K of zero; ceramics are a totally different beastie) in school and got diverted into reading up on ultracryogenics for a few weeks - apparently at temps that low, you get all sorts of problems like extreme brittleness and differing rates of thermal expansion, the latter being a fairly major issue in designing an ultracryogenic system. There's a good chance the CPU die, wires, and case would all tear away from each other and destroy the thing. Not to mention that lead superconducts at 7.196K; i wonder what resistanceless solder would do to a mobo...

Exciting research into superconductivity using carbon nanotubes coupled with the space elevator using carbon nanotube based cable would lead one to the conclusion that they should use a set of parallel cables/conductors, abondon the whole laser lights the elevator to get it power concept and just pas the power through the elevator cables, with the excess delivered to the ground.

Don't these scientists talk to each other or leverage each others work? This is why we are not getting to space at an acceptable pace while solving rather than causing problems on the Earth as a result ... IMO.

That doesn't make it less of a scam though, it just means that there are some very trashy journals who have very low standards for referee selection. And, calling the author a "scientist" is probably a bit much of a stretch.

I even came across a theoretical paper demonstrating that the effect can exist, given the right conditions. The abstract stated boldly that the effect is a natural consequence of relativity plus some quantum effects, without stating that the model of gravity they were using was completely artificial, I think Euclidean space with massive gravitons and lots of other weirdness. (For the non-physicists, having massive gravitons means that gravity would decay exponentially fast, rather than the usual inverse-square law). Indeed, the paper served as a good demonstration that it is very unlikely that such an effect could happen in reality.

By the way, i don't think NASA gave him 1 million, I think rather they spent that trying to reproduce the experiment themselves. I vaguely remember a story that he was the only one who knew enough details to repeat the experiment, so NASA ended up getting him involved (which basically amounts to giving him the million, I guess).

The only other case that springs to mind of an experiment where only one person can "reproduce" it, is (ahem) Jan-Hendrik Schon.

...maybe we could just lock in the coordinates on our freight transporter and teleport it directly into the sun. You're thinking 1000 years, not 100. Think of what we have accomplished in the past 100 years and stop being ridiculously optimistic.

As I understood, those hoverboards were powered by superconductors, but again there would be a temperature issue there.

The discovery has no immediate practical value but is important because it adds a new dimension to the study of superconductivity, Stewart said.

"You can't make practical materials out of something as radioactive and chemically poisonous as plutonium," he said, "but John Sarrao and this collaborative team have made a big leap in understanding superconductivity from a fundamental point of view."

The discovery has no immediate practical value but is important because it adds a new dimension to the study of superconductivity, Stewart said.

"You can't make practical materials out of something as radioactive and chemically poisonous as plutonium," he said, "but John Sarrao and this collaborative team have made a big leap in understanding superconductivity from a fundamental point of view."