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A New Family of High-Temperature Superconductors

Posted by kdawson on from the mister-nobel-to-a-white-courtesy-telephone-please dept.

sciencehabit writes to let us know that physicists are hailing the discovery of a new type of superconductor as a "major advance." The new materials could solve the biggest mystery in condensed matter physics — i.e., how and why cuprate superconductors work — as well as paving the way for practical magnetic levitation and lossless transmission of energy. "God only knows where it will go," says one Nobel Laureate. After the discovery of superconductivity in an iron-and-arsenic compound at 26 kelvin, several Chinese research groups quickly found related materials that are superconducting up to 55K. (Cuprates go as high as 138K; liquid nitrogen boils at 77K.)

9 of 113 comments (clear)

  1. Re:Hot! by Ctrl-Z · · Score: 4, Interesting

    The "firestorm" was ignited by the discovery of cuprate semiconductors, which "have critical temperatures in excess of 90 kelvin"[1], which is above the temperature of liquid nitrogen.

    [1]http://en.wikipedia.org/wiki/Superconductor

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  2. Re:Hot! by jellomizer · · Score: 4, Informative

    Well there is a huge difference in the price for using Liquid Nitrogin vs. Liquid Helium. Right now for superconductors used in MRI's they use Liquid Helium at 4k. And they use Liquid Nitrogin as an insolator to protect caseing from cracking. At roughly $1000.00 per leter of Liquid He, Liquid Nitrogin is much cheaper. Anf if they can get to a point where you can maintain superconductivity at Dry Ice level it would cause far more advances in society.

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  3. Re:Hot! by ThreeGigs · · Score: 5, Informative

    The excitement isn't about superconductivity at 55K by itself. It's got everyone excited because, *finally*, there's something besides cuprates that superconducts above about 33K (which defines high temperature in the superconductor world).

    Now, instead of having just one 'family' of HTSC materials to base hypotheses and theories upon, scientists now have TWO. Now they can compare similarities and differences between those two families. This gives them a HUGE boost towards figuring out the exact mechanism involved, plus potential leads on new materials that exhibit similar atomic structure which could also superconduct.

  4. Re:Is this really news? by Andy+Dodd · · Score: 4, Insightful

    It is news not because of any new temperature records, but because of the fact that these are the first superconductors outside of the cuprate family to exhibit high critical temperatures.

    This is an entirely new family from the cuprates. The cuprates started much lower too. Also, even if this family never compares to the cuprates in performance, the behavior of this new family could shed light on the (relatively unknown) mechanisms of cuprate superconductivity, allowing for that family to be developed further.

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  5. Re:US science is dying? by What+Would+NPH+Do · · Score: 4, Insightful

    I am more interested as to why American scientists weren't the first in on this, Because despite the jingoist tune, the US hasn't been the forefront of technology and science for quite some time. When you have creationists trying to ruin science education all across the country it's not that surprising.

    and why such cutting-edge research is being done in China (a poor third-world country). China is poor? Since when? They're raking in the dough which is why they also hold 1/3 of the US national debt. Besides, countries in Southeast Asia have been pumping out cutting edge research for years now. If you were to shed the chauvinism for a few hours you might have noticed this already.
  6. Re:Hot! by evanbd · · Score: 4, Informative

    Where do you get $1k/L? A quick google search turns up $3-5 per liter, which is about what I recalled. LN2, of course, is much cheaper -- $0.25 in small quantities, $0.05 per liter or less in very large quantities.

    Dry ice is more expensive than LN2, because you have to pay for the CO2, rather than just liquefying air. But if you don't actually need dry ice, then dry ice temps are certainly cheaper to reach than LN2 temps.

  7. Re:US science is dying? by Anonymous Coward · · Score: 5, Informative

    If you think China is a poor third world country then you are going to be shocked.
    China is mostly a second world country

    "First world", "second world", and "third world" are not some ranking of affluence. "X world country" was an old Cold War term. First world nations were those aligned with the West. Second world nations were those aligned with the Soviets. Third world nations were those aligned with neither. Since the fall of the USSR, there is no longer such thing as a second world country.

    Third world countries tended to be poor and underdeveloped. Now "third world" has become synonymous with "poor", but it is really a misnomer.

  8. Re:Hot! by krlynch · · Score: 5, Informative

    At roughly $1000.00 per leter of Liquid He, Liquid Nitrogin is much cheaper.


    You've got the right idea, but your numbers are a bit out of whack ... LN2 is about $0.10/L in large quantity, while LHe is about $3-20/L, with large variation in price around the world (due to constrained supply and large transportation and energy costs). US He is relatively cheap, as we have a few of the small number of high quality sources. In Europe, He is very much more expensive, as they don't have any local, high quality sources. A recent compilation of costs is available here: http://hypertextbook.com/facts/2007/NadyaDillon.shtml

    Helium is so expensive, because it is very entery intensive to liquify, and it isn't commercially extracted from the atmosphere like nitrogen ... there just isn't enough of it to be commercially viable. Instead, it is generally found in pockets underground and "mined". The helium originates as alpha particles in the decay of radioisotopes (mostly Uranium and Thorium), and permeates through the crust. It gets trapped in high pressure gas pockets by impermeable rocks, in the same types of geology that trap natural gas, and is extracted for commercial scale from those pockets. There are only a few global sources where the concentrations of helium are high enough to extract economically.
  9. Re:Hot! by DieByWire · · Score: 5, Funny

    The article specifically mentions 138 kelvins as the highest temperature where cuprates still hold on to superconductivity. That's roughly -115 degrees celsius.

    I believe you mean -135 degrees celsius.

    That last twenty degrees is what keeps Minnesota from superconducting in winter.

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