Metamaterial Superconductor Hints At New Era of High Temperature Superconductors

KentuckyFC writes: Superconductors allow current to flow with zero resistance when cooled below some critical temperature. They are the crucial ingredients in everything from high-power magnets and MRI machines to highly sensitive magnetometers and magnetic levitation devices. But one big problem is that superconductors work only at very low temperatures — the highest is around 150 kelvin (-120 degrees centigrade). So scientists would dearly love to find ways of raising this critical temperature. Now a group of physicists say they've found a promising approach: to build metamaterial superconductors that steer electrons in the same way as other metamaterials steer light to create invisibility cloaks. The inspiration for the work comes from the observation that some high temperature superconductors consist of repeated layers of conducting and dielectric structures. So the team mixed tin — a superconductor at 3.7 kelvin — with the dielectric barium titanate and found that it raised the critical temperature by 0.15 kelvin. That's the first demonstration that superconductors can be thought of as metamaterials. With this proof of principle under their belts, the next step is to look for bigger gains at higher temperatures.

Comments

0.15 degree from a 3.7 kelvin... that's "cool"

[JcMorin]

I feel it's soo far away to be somehow useful I'm not that excited.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[Shortguy881]

Think of the flying cars!

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[JoshuaZ]

This is extremely preliminary. It is likely that later work will be able to increase it further. And even an increase in a few degrees centigrade would have practical impacts. Moreover, the ability to make metamaterials of this sort may lead to superconductors with different ranges wherein they engage in magnetic quenching https://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_quench which is important for safe and practical use of superconductors even today. It isn't uncommon for a bad quenching event to damage a particle accelerator. A particular bad example happened to the LHC back in 2008 dealing serious damage to the accelerator http://astroengine.com/2008/10/18/lhc-quench-ripped-magnets-from-concrete-floor/. Yes, this isn't immediately practical but it looks like there's a lot of potential.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[Anonymous Coward]

... but we have flying cars. You can order one now. They're actually quite competitively priced compared to small planes in the same class.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[Anonymous Coward]

This was just proof of concept on an already awful superconductor.

This was triply important in fact:
1) proof that it works
2) thinking of superconductors as metamaterials could allow very high temperature superconduction
3) it was even tested on a crappy superconductor, which tested the waters for the expected gains.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[ShanghaiBill]

... but we have flying cars. You can order one now.

You can buy a roadable aircraft that can be driven to and from an airport. That is not the same as a real flying car that can takeoff and land on my driveway. It would also be cool if it could fold up into a briefcase, like it did on the Jetsons.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[l0n3s0m3phr34k]

You just need a longer driveway!

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[meerling]

They've been stuck for how to increase the temperature range for some time now. Despite this being a tiny increase, it's a huge thing as it shows an entirely new way to increase temperature ranges that actually works.

Re:0.15 degree from a 3.7 kelvin... that's "cool"

[WindBourne]

No doubt that is what ppl like you said when the wright brothers flew about 100' just over 110 years ago.
And it is the same thing that was said by others like you when America made the lithium Batteries.
Or when Goddard flew the first liquid rocket.

It is obvious that important issues escape you.

150 kelvin = -189.67 F

[Flavianoep]

You're welcome.

Re:150 kelvin = -189.67 F

[GNious]

C'mon, it is the year 2014 already - no-one uses Fahrenheit any longer.

Re:150 kelvin = -189.67 F

[Flavianoep]

And about the USA?

Re:150 kelvin = -189.67 F

[Anonymous Coward]

Because they are pig headed. Kids are taught metric system in school, but encouraged to use British Imperial - which, coming from the US, is kind of ironic.

Re:150 kelvin = -189.67 F

[mark-t]

It's especially ironic because in Britain, they actually use the metric system.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

Also, we haven't used the term centigrade in 50 years.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

No agrument that you should use metric units for technical work, but for day-to-day temperatures I still prefer Fahrenheit (which scales 0-100 to cover the temperature range normally experienced outdoors).

Knowing that today's high will be in the 50s/60s/70s/80s/90s/100s conveys info in a user-friendly way (to me at least).

I noticed that the thermostat in my last European hotel room allowed temperature adjustments in 0.1 increments, which suggests the Celsius scale is a bit too coarse for daily use.

Re:150 kelvin = -189.67 F

[lgw]

Fahrenheit is the only temperature system anyone should use! It's the temperature component of the One True System of measure: the Fortnight-Firkin-Furlong system.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

So if a 13 stone man walks two miles to the pub for a pint, he's no longer in Britain?

Re:150 kelvin = -189.67 F

[meerling]

I'm in the USA, and when I was in grade school back in the early 70s (!) they only taught us the Metric system. To bad I was forced to halfway learn that piece of crap Imperial system because almost nobody else in the country would use it. For some reason they seem to think 16 sixteens to an inch, 12 inches to a foot, 3 feet to the yard, 1760 yards in a mile is easier than a system where everything is based on 10. (I had to look up the feet/yards to mile, and so do most people, even the ones that don't know metrics.)

If you ask me, 10 millimeters to a centimeter, 10 centimeters to a decimeter, 10 decimeter to a meter, 10 meters to a decameter, 10 decameters to a hectometer, and 10 hectometers to a kilometer, and so on is just bloody easy.

If you want to convert millimeters to kilometers, it's dead simple as it's just operations of 10, which you might be more familiar with as moving the decimal point depending on your math classes. And by the way, that is 1,000,000 millimeters is one kilometer, no calculator needed for such a simple conversion.

Now for your next trick, try converting 16ths of an inch to a mile. I'm not sadistic, you can use a calculator, and good luck. :P

Re:150 kelvin = -189.67 F

[WindBourne]

Actually, Britain uses a mix of metric and imperial. They still refer to their weight in stones, amongst others.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

I noticed that the thermostat in my last European hotel room allowed temperature adjustments in 0.1 increments, which suggests the Celsius scale is a bit too coarse for daily use.

It isn't. There is no reason for the temperature adjustment to be in 0.1 increments other than technical snobbery. I doubt it even could measure the temperature accurately down to 0.1 degrees Celsius, and I'm very certain that it couldn't regulate that temperature evenly across the room.
If someone was talking about half degrees Celsius I could buy that, but if someone claims to notice the difference I call bullshit unless they are talking about noticing water freezing.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

But we use the metric system for temperature, which is the relevant part to this discussion. Sheesh.

Re:150 kelvin = -189.67 F

[Anonymous Coward]

Who gives a flying fuck what a git like you does? The fact is, that limeys use BOTH systems, just like America does. Those of us in the science world, use metric. In the medical, it is imperial. In business, it is imperial. So, this is not much different than you do.

Re:150 kelvin = -189.67 F

[leonardluen]

if you are converting miles to 16ths of an inch you are doing something wrong.

really there isn't much need most of the time to convert between miles and inches or even feet and miles. the only real reason for that is to compress the number when you write it down. there is nothing stopping you from using deca-feet or kilo-feet.

typically when you are working in miles you aren't measuring down to the foot. so you would say something is 3.5 miles not 3 miles and 2640 feet or 3 miles and 880 yards.

the imperial system is designed around construction. using either feet or yards as our base unit for construction we can easily divide it into many different factors using inches. want something to be 1/3rd of a foot? easy that is 4 inches. now try doing that with metric.

really the imperial system (for distance) has multiple different measurement scales it just so happens that we designed them so we can easily scale between them. metric only has one. the meter with multiple prefixes we can attach to it. i will grant you that metric is far better for most scientific measurements. and when you get to relativistic speeds and stellar distances the imperial units mean nothing to me, i need to see it in metric to get a proper sense of scale.

now i am not by any means against metric, i just don't loath the imperial system.

however at relativistic speeds and stellar distances your precious metric system sort of breaks down. how many kilometers in a light year? you can use a calculator, and good luck. :P

*well i guess light year isn't really a metric unit but it is a commonly used scientific unit of measure, and does not easily convert to meters.

Read that as Metamucil Superconductor...

[MrSavage]

I thought, "Wow! Now that's got to be really fast acting!"

Miracles^2!

[Thud457]

You just made 37 Juggalos' heads asplode.
Good work!

I'm not terribly impressed.

[mark-t]

So they raised the critical temperature of a substance 3/20ths of a degree K above what it is otherwise, and the substance wasn't even among the category of what are considered high temperature supercondutors currently. Color me incredibly excited about this when they can raise the critical temperature of a superconductor to something like the freezing point of water... or even dry ice for that matter.

Re:I'm not terribly impressed.

[Anonymous Coward]

I believe in 2011 or 2012 some japanese scientists made some iron compound superconducting using red wine and other alcoholic beverages.

Clearly we have not explored all the options ;)

Re:I'm not terribly impressed.

[Anonymous Coward]

High-temperature superconductors will become common when "ordinary" cooling is sufficient. Dry ice is impractical, that doesn't count. Can't pump it. In this case, we can make "ordinary cooling"concrete. Liquid nitrogen is too cold (77K); it causes condensation of nitrogen from the air. That's too bad because high-temperature superconductors still superconduct at the boling point of N2. But ethanol is a realistic coolant; it freezes below 159K. Propanol is even better at 147K.

Unfortunately we don't have any superconductors which still work at those temperatures. And coolants for 100K are a major problem - there's simply not a lot which boils at those temperatures, nor are there many fluids with a decent heat capacity at 100K. We'd simply need too many tons of coolant.

Re:I'm not terribly impressed.

[mark-t]

I mentioned dry ice as an example not because you'd use dry ice to cool a superconductor directly, but because the temperatures necessary to make dry ice can be very easily achieved with inexpensive refrigeration techniques.

Re:I'm not terribly impressed.

[Anonymous Coward]

Somebody just needs their grant money.

Re:I'm not terribly impressed.

[Anonymous Coward]

Each "stage" of cooling needed, as temperatures rise, brings about a dramatic lowering of costs. The stages correspond to common coolants and are essentially:

Liquid hydrogen (-253 C)
Liquid nitrogen (-196 C)
Liquid oxygen (-183 C)
Solid carbon dioxide (-78.5 C)

At least I think I've got that right. All those should be for 1 Atmosphere pressure regimes.

Re:I'm not terribly impressed.

[AC-x]

Still, that represents a 4% increase in temperature, and also a completely new theory on why superconductors actually work.

Re:I'm not terribly impressed.

[nmr_andrew]

Frankly, I think we (meaning: those who design these sorts of things for a living) can deal with the issue of condensation out of the air.

The big problem today is that so-called "high temperature" superconductors all have less than desirable properties. Some are amazingly fragile; some superconduct but can't really be worked/machined in any meaningful way; some are so difficult to make (at least reproducibly) that they can't be used for anything more than research. It's great we've gotten this far.

As a practical thing, most of us who make use of superconductors would be absolutely THRILLED if we could get a good, workable, and ideally strong superconducting material that operated even a little bit above LN2 at 77K. Any remotely useful supercon material needs to be cooled with liquid helium, which is both non-renewable and expensive. Our little NMR facility (3 magnets) spends over $30k/year just keeping the magnets cold so they can be used as something more than very expensive paperweights. And we actually get a "good" price on LHe.

I never ...

[CaptainDork]

... metamaterial I didn't like and stuff.

Not impressed.

[Anonymous Coward]

But when they raise the critical temperature by 0.20, THEN I'll be impresses.

Also known as -123.15 C

[AC-x]

...