Slashdot Mirror
New Type of Superconductivity Spotted
sciencehabit writes with this excerpt from a story about research into an unusual form of superconductivity:"Superconductors, materials that carry electricity without resistance, can be divided into two broad groups depending on how they react to a magnetic field — or so physicists thought. New experiments show that one well-studied superconductor actually belongs to both groups at the same time. The advance may not immediately lead to new gadgets and applications, but it suggests that superconductivity, which has already netted four Nobel Prizes, may be an even richer phenomenon than previously thought."
But is it going to work at Room Temperature?
Ah, the elusive super-zwitter-conductor finally appears!
Wasn't that what the engineers in the movie Primer (trailer) were working on?
Sorry, I just watched that for the first time earlier this week and am still enamored with it.
Faith is a willingness to accept something w/o complete proof and to act on it. Reason allows you to correct that faith.
A room-temperature superconductor would be nice, but even with today's superconductors a hell of a lot can be done...in space!
With all this talk of inter-planetary space travel, space provides the right temperature without expensive cooling systems. Simply insulate the superconductors from direct sunlight and you get great applications like passive superconductor magnetic bearings and other cool oddities that you would only get with expensive cooling systems here on earth.
Space isn't really cold... And any heat built up would need to be radiated away, not removed through conduction or convection. I'm not very well versed in this all, but I expect these limitations would actually make it hard to do all that much with...
actually, it could be very easily conducted away using some material, and then radiated (from heat sink-like things).
and to think, i could get modded insightful sometimes if i bothered to use proper sentence structure...
Heat buildup from what, electrical resistance?
While true, this is not "easy" -- radiative cooling is very restrictive, and you get no conductive or convective cooling in space.
Heat buildup from what, electrical resistance?
Oh snap!
It's sometimes hard to see it from Earth, but it turns out there is a really large glowing ball out there sending heat in a directions.
I, for one, wonder how the hardcore Christians will react when they find out God created bisexual superconductivity. :-)
Be relentless!
So? Ever heard of Stokes' theorem?
superconductorsgobothways
What?
A hell of a lot can be done with todays superconductors without the added expense of launching them into space. The point of room temperature superconductors is to get them cheap and ubiquitous.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
they're biconductors?
Yeah, and one side of a spacecraft is going to be colder than the side facing the Sun. I wonder where all the excess flux goes?
Actually, that large glowing ball is sending light in all directions. When said light strikes mass, the mass is energized and heat is produced. Heat doesn't travel through a vacuum.
Once in place and insulated from sunlight and physical contact from the insulator (along with anything else that might generate heat), maintaining a material at superconductivity should be no problem. The hard part is getting it to superconductivity in the first place. I think you'd have to send it out into space already at superconducting temps, wouldn't you?
The shade will heat up, then emit IR radiation, which is the light that causes that heat in the first place. All bodies radiate, how much depends on their temperature.
Not a sentence!
Schrodinger's superconductor!
I shall answer this by invoking the usual "fixed it for ya" slashdot mantra, thus:
"I, for one, don't need to wonder how the hardcore Christians will react when they find out the devil created bisexual superconductivity in a vain attempt to tempt them away from the lord."
The revolution will not be televised... but it will have a page on Wikipedia
Even at that, you can ignore space or room-temperature superconductors.
Right now, there are a considerable number of devices that require superconductors at liquid nitrogen or liquid helium (~2 K) temperatures. You won't find them in your home, but you will find them everywhere at the cutting-edge of scientific research (medical imaging, particle accelerators, etc.)
The prospect of being able to make these devices cheaper, smaller, or more powerful is extremely enticing to the operators of these devices. Cooling something with liquid helium is insanely difficult and expensive.
If a device requires liquid Helium, you can be assured that its operators have extremely deep pockets, and are funding research to eliminate or reduce the need for liquid Helium cryogenics. To say the least, maintaining a device at 2 Kelvin is rather costly.
If the LHC could run at room temperature, it'd cost a mere fraction of what it does.
-- If you try to fail and succeed, which have you done? - Uli's moose
Space isn't really cold...
"Ambient" Temperature in space from background radiation is around 3 Kelvin
Solar irradiation at altitude is roughly 1,500 watts/sq-meter which is about 5000 btu's, or what a small electrical space heater pumps out.
So, envision a space heater (and of the radiant type, if you prefer) radiating its little heart out towards a square meter of shiny white aluminum which is also radiating outwards to a vast, lonely, empty space with a background temp of near 3 K... That's gonna be a sad little piece of metal now, which thanks to this thought experiment, would be freezing its shiny non-ferrous butt off.
A LOT of heat can be radiated by an object, the only reason why we don't encounter it much as a phenomenon on earth is that the ambient environmental temp is not much cooler relative to whatever object is hot, such that the rate of heat loss, dependent upon the temp delta, is minimal. The two systems just end up swapping a lot of IR back and forth. This doesn't happen when the background is near zero kelvin.
Heat doesn't travel through a vacuum.
Er... what? Heat can pass through a vacuum perfectly well as electromagnetic radiation. I was warmed from the sun today.
If the LHC could run at room temperature, it'd cost a mere fraction of what it does.
And it would've been done 3 years ago, since you don't have to warm-up and cool-down to fix every damn little problem, or train (heat/cool cycle) the magnets to get to the desired field strength.
Don't you just love it when a bunch of pedantic nerds get hold of a subject like this? They all try to shoot each other down by finding ever smaller, ever more pathetic flaws in their predecessor's argument, when the truth is most of them have no more than a passing knowledge, probably gleaned from the Discovery Channel.
It's like the "5 scifi geeks clustered round a broken laptop" syndrome. None of them actually knows how to fix it, but they're damn well going to try, and tell everyone else how stupid their own approach is to boot. I just sit back and watch :)
BTW: Not trying to troll, although I realise this post kind of reads like one. I just get frustrated sometimes by the lack of perspective apparently suffered by some people in groups like this.
Nobody else has this sig.
It would still have to be insulated from sunlight: almost any material would absorb more radiation from the sun than it would emit through radiation at ~3K, and thermal equilibrium would almost certainly happen at a much higher temperature than would allow for superconductivity.
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It was only a matter of time until the Lesser Spotted Superconductivity was twitched upon.
Slashdot might be called news for nerds but I can assure you that there are a host of non-nerd types haunting the forum, government agents, government propagandists, marketdroids, intellectually handicapped failed jock straps all filling the forum with all sorts of rants, makes it more interesting.
Generally speaking an exchange of ideas is what /. is all about, so when you exchange, you are in fact exchanging correct ideas for faulty ideas, so obviously some posts will be wrong and upon correction people will revise their ideas and, often by creative leap feed back into the forum new ideas.
Of course when it comes to room temperature superconductivity, it should be obvious that no one has the right idea, so everyone throws in a bunch of wrong ideas think about the faults and via that creative process try to come up with the more correct ideas that will eventually lead to a solution. When it comes to the interplay of ideas, right wrong or indifferent makes little difference to nerds/geeks, playing with those ideas, formulating new creative thoughts and, of course the brain chemical rewards while lost in those thoughts are the purpose, perhaps you are missing out on those endorphin rewards that a lot of /.ers get.
Superconductivity, hmm, electron flow within in turbulent electron fields, eliminate the turbulence from the electron fields and you have smooth flow, any turbulence and you disrupt flow which increase turbulence and further disrupts flow, energy build up is released as photons to achieve equilibrium. So superconductivity is all about creating smooth electron fields to facilitate the flow of electrons and the prevention of the build up of turbulence. Micro structures, perhaps molecular toroids or channels are the most likely route to a solution, so micro channels on the inside surface of a conductive conduit would be an interesting idea to pursue, after all as long as it is super conductive you don't need very much material to provide the required conductivity.
Chaos - everything, everywhere, everywhen
yeah, like in predator
>>All bodies radiate, how much depends on their temperature. so their temperature depends on their temperature? who would have thought that...
Physics: FAIL
Try taking apart your termo insulated can - its using vacuum
I don't know why we're so obsessed with moving electrons. Wouldn't it be easier to move sub-atomic particles instead?
you don't know the difference between heat and energy, and you've made yourself look like a retard.
Common sense: FAIL
The two sides (in and out) of your can are only at a few hundred Kelvin, and the rate of IR leaving one side for the other is very low (and being only a few Kelvin apart, the net rate is going to be even lower). The sun, however, is at a few million Kelvin, and thus sends out IR at a much higher rate.
Actually, he's just being pedantic.
Thermodynamically, heat is a property of a body with mass (I'm ignoring quantum fluctuations here, and averaging over time), measured as the average vibrational energy with respect to the degrees of freedom of a body's constituent matter. (As we approach absolute zero, the wavelike aspects of matter makes this less sensical; Heisenberg's uncertainty principle, a property of waves, means that position becomes very indeterminable as momentum becomes well-defined. We don't need to worry about this much, though, when studying basic thermodynamics.) Photonic energy is generated by any hot (meaning above absolute zero, which everything in the universe necessarily must be, by definition) bodies in a radiative process and absorbed by adjoining bodies.
This is why most people think IR is heat; however, is the orange glow of a flame heat, or is it the radiative light given off by the combusting fuel and air/oxidizer?
Radiated IR is not heat. It is the body radiation of matter that is undergoing the motive process of being in any hot state. Collisions among molecules, ions, and bonded and unbonded atoms are not perfectly elastic; sometimes one of the particles will be pushed to a higher energy state, and this is energy is subsequently radiated as a photon.
Kinetic energy (classically m*v^2/2) and photonic energy (h*nu) are both forms of energy.
(Posting anon because I know a physics expert is going to come in and nitpick and make me look... like a retard *grin*)
Actually, you are wrong.
Radiated IR is heat
Technically, heat is the energy exchanging between bodies due to their difference in temperature. If it's not moving, it's not exactly heat.
What are you doing here on /. , traitor?
superconductors is for CPU/GPU chips. If we can finally get a material that's easy to work with, we'd finally be able to get damn CPU speeds in excess of 10GHz, which is what the P4 (netburst) architecture was designed to do.
The question then becomes, what do we do with such high speed chips? and the answers include Voice Recognition, Speech Synthesys, better pron (ray traced) and maybe Duke Nukem forever. Of course I can safely state that Windows 9 would certainly need such a CPU along with Symantec (NAV) just to handle the bloated slug those apps have become.
Mod me up/Mod me down: I wont frown as I've no crown
Heat can pass by convection, and heat can pass by conduction,
and heat can pass by radiation, and that's a physical law!
Heat is work, and work's a curse.
And all the heat in the universe,
is gonna COOL DOWN!
Cos it can't increase, so there'll be no more work
and there'll be perfect peace.
Really?
Yeah, that's entropy, Man!
That definition of heat which you have given is commonly stated in physics or thermodynamics textbooks, and for most things, it's perfectly correct. I really should not have used the words "basic thermodynamics" in the grandparent post, because, yes, as you've stated, photons are a form of heat as the word "heat" is used in thermodynamics. I should have made much more clear the context of my pedantry. ;) I'm just tired of all the people who have the misconception that the molecules in a solid object at room temperature are sitting still, and that there's this magical thing called "IR light" that hot things are somehow full of.
However, you don't hear the term "heat" used unqualified very often in academic literature without some sort of meaningful context. In the English language, heat has dozens of definitions, and you can guarantee that your research will be misunderstood if you say something that might have slightly different meanings to chemists, mechanical engineers, cosmologists, particle physicists, solid-state electronics designers, etc. That's why it's almost always given with a certain context and is typically found in a phrase such as "heat transfer," "heat capacity," "specific heat," etc., which all have very explicit usage and meaning. When most people casually refer to heat, they are referring to the internal energy, a sum of the kinetic energy (actually a very complex thing; the simple water molecule has six vibrational modes) and latent energy from the arrangement state and material phase (again, water has more fun behavior to offer). When most people refer to light, they are referring to a collection of photons. The energy associated with the process of heat transfer is a quantity, whereas photons are a physical object. Quantities and physical objects are not interchangeable in language.
(This whole problem of communication is made even worse by adjectives like "hot," which often refers to temperature, a quantity with a distinctly different nature and meaning than "heat.")
This is really a question of usage and semantics. I would say that light can impart heat to a substance, but photons themselves are transfer particles. Heat transfer is known through three processes, conduction, convection, and radiation; in a specific temperature range, the energies of most photons radiated from an object with perfect emissivity (a black-body) fall into the FIR range. I think conceptually, though, it's a lot better for someone to think of heat as molecular movement and light as electromagnetic particles with a definite energy corresponding to their frequency; explaining to most people that one mechanism of heat transfer that brings bodies into equilibrium is the exchange of photons with energies corresponding to the absorption spectra (ignoring fluorescence and similar phenomena here) of said bodies--but that heat on a molecular level is typically considered a function of particulate motive behavior--only seems to confuse many people, reinforcing the misperception that hot things are hot because they're full of infrared light that slowly leaks out. You would not BELIEVE how many people think something like this.
Er...and the medium they are in. I would lose body heat faster in the sea than in space, because of the volume of colder material and it's shape-conforming nature.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
I wonder where all the excess flux goes?
Into the capacitor, duh.
Its all fun and games until suddenly, superconductivity is banned.
That is conduction, not radiation. You don't radiate more heat in the sea than in space.
Ah, fair enough.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
Heat doesn't travel through a vacuum.
Oh, so THAT's the reason the electromagnetic spectrum between microwaves and visible light is always blacked out and ignored. Infrared is the polywater of the EM spectrum...
Tag lost or not installed.
Common sense: FAIL
The two sides (in and out) of your can are only at a few hundred Kelvin, and the rate of IR leaving one side for the other is very low (and being only a few Kelvin apart, the net rate is going to be even lower). The sun, however, is at a few million Kelvin, and thus sends out IR at a much higher rate.
Perhaps you're thinking of the inner core where fusion takes place. The surface, which is what radiates heat, light and other things to Earth, is not nearly as hot. One online figure is 5777k:
http://en.wikipedia.org/wiki/Sun
The rest of your point is still valid, radiation isn't nearly as effective at moving heat as are conduction and convection, and that's why a Thermos bottle works.
Tag lost or not installed.
Ok. its a bit brave to nominate myself as an expert, but I work in this field and spent many years studying this compound (this material was the subject of my PhD thesis). I am a slashdot noob though... Firstly, I am a bit surprised that this kind of article got slashdotted. The new PRL 'Viewpoint' section which covered this may have helped. Secondly the evidence for the new state doesn't seem that convincing to me yet. A non-uniform, imperfect flux line lattice (as they observe) is the norm in most materials due to pinning of vortices at impurity sites. The comparison material in their paper (NbSe2) is often studied because of its unusually well behaved lattice, which looks like the textbooks. I would like to see the numbers that they calculate for the apparent 'lumpiness' of the vortex lattice in a range of other superconductors before I drew any conclusion. Finally, the estimates that they claim put them in the regime of 'type 1.5' are only valid in the clean limit. Impurity scattering, which enhances the penetration depth somewhat, changes these figures. I would say that the experimentally determined penetration depth is larger by a factor of two or three (although these are subject to some uncertainty) which makes the picture quite different, pushing you further towards type II. Anyway, thats my comment. PP