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Scientists Create Supersolid From Helium
jabberjaw writes "Nature is reporting that Pennsylvania State University researchers Eun-Seong Kim and Moses Chan have created a 'supersolid' from helium-4. Although a crystalline solid, the supersolid can flow much like a liquid. This is due to the fact that the empty compartments in the crystal move coherently, thus waves can progress through the lattice. The supersolid state can be compared to the superfluid state. Perhaps a condensed matter physicist can dumb the article down for layfolk such as myself?"
Joyous helium
Becomes a supersolid
At low Celcius
But seriously, this stuff is really cool. What with the properties they described, I wonder if it could be useful in conducting electricity or forming a shock-absorbing barrier?
Cyde Weys Musings - Scrutinizing the inscrutable
My dad did his PhD thesis on liquid helium 3. Apparently it's pretty difficult to contain the stuff, since even the tiniest opening in a container is enough for everything to escape at once (no viscosity)...
Next generation viagra additive?
Sure it could be. Here's the abstract from Eunsong Kim's talk about it two days ago at Penn State University, courtesy of our friend Google:
When liquid 4He is cooled below 2.176 K, it undergoes a phase transition--Bose-Einstein condensation--and becomes a superfluid with zero viscosity. Once in such a state, it can flow without dissipation even through pores of atomic dimensions. Although it is intuitive to associate superflow only with the liquid phase, it has been proposed theoretically that superflow can also occur in the solid phase of 4He. Owing to quantum mechanical fluctuations, delocalized vacancies and defects are expected to be present in crystalline solid 4He, even in the limit of zero temperature. These zero-point vacancies can in principle allow the appearance of superfluidity in the solid. However, in spite of many attempts, such a 'supersolid' phase has yet to be observed in bulk solid 4He. Here we report torsional oscillator measurements on solid helium confined in a porous medium, a configuration that is likely to be more heavily populated with vacancies than bulk helium. We find an abrupt drop in the rotational inertia of the confined solid below a certain critical temperature. The most likely interpretation of the inertia drop is entry into the supersolid phase. If confirmed, our results show that all three states of matter--gas, liquid and solid--can undergo Bose-Einstein condensation.
I heard about something like this a few years back, as I understood it then the thing is that at low enough temperatures atoms break down into a "soup" of protons, neutrons and electrons all behaving like a liquid.
I think what you're describing is a Bose-Einstein condensate, which is something entirely different.
Cyde Weys Musings - Scrutinizing the inscrutable
I just laid a supersolid one. Yeah I posted anon.
This is not the first new state of matter announced this week.
/. but keep forgetting password...
. ht ml
The New York Times reported a "color gass condensate" when gold ions were bombarded with relativistic deuterons. In this condition, nucleons and quarks blur into a jello of gluons.
There are MANY more states of matter than solid, liquid, and gas. There's plasma, 2-dimensional fluids, 1-dimensional crystals, ambiplasma of partcies and antiparticles, photon crystals, and lots of others.
This is the golden age of physics!
Professor Jonathan Vos Post
Woodbury University
have an accounton
BTW, check out my "Periodic Table of Mystery Writers" at
http://magicdragon.com/UltimateMystery/periodic
rollovers and click to 100+ pages...
when you misread the title as "Scientist creare supersolid human"
Kind of a nice idea though...
I'm going to sleep now.
Great news. Now we can understand how the T1000 works!
I hope they'll build one soon; it could be a great war machine AND sex toy
A superfluid is a fluid that flows without viscosity, meaning that if you were to stir a spoon in a superfluid soup, you could take out the spoon and the soup would keep swirling forever on, since there is no mechanism there (i. e. no friction) to make the vortex you just made disappear. Now if you were to cool a 4He crystal, there would be eventually be no more movement of atoms and the whole thing froze out. But in quantum mechanics, there is the Heisenberg uncertainty Principle which basically states that you are not to now the position of any particle along with its velocity with the same accuracy. There will always be a trade off. The better you know the position, the worse you know the velocity. This accounts for the fact that even at absolute zero, there are some fluctuations of particles, called quantum fluctuations wich do never freeze out. When a superfluid appears this means that the atoms in it move all together. As the Nature article suggests, you can compare this to soldiers on a parade. They all move alike. In a supersolid then, you have vacancies, places where atoms are absent. Think of holes in a semiconductor if you like. There, holes are just non-electrons. Here we deal with non-atoms, and they are the ones behaving like soldiers in the case of a supersolid. Meaning the propagate through the whole thing as if they were on a parade, which makes them great for sending any wave (electromagnetic or other) through the crystal, and since these vacancies move in order, they propagate the wave without damping it. This would make a hell of an amplifier. Compare the situation to a superconductor, where you can propagate electric current without damping (i. e. having no resistance at all). To electric current, a superconductor behaves like a supersolid to waves of any kind.
Black holes were created when god tried to divide by zero
That's a fallacy. The flow rate of ordinary plate glass is so slow that it would take billions of years before there would be a measurable change in thickness. Here are some articles on the subject.
Sapere aude!
In actuality, superfluids do NOT have zero viscosity at all points. They have very complex properties, depending on a combination of the container, exact conditions, etc, etc. Typically, some parts of superfluids exhibit zero viscosity (truly zero), leading to some fascinating fluid mechanics. For example, the Stokes singular problem actually has NO boundary layer, so drag goes to zero. There are plenty of other really interesting phenomenon - some that might be utilized in future technology.
Other interesting properties of superfluids include rather odd magnetic fields (Helium-3 or 4 is odd to start with, and then chilling it down and spinning it does some interesting stuff), VERY odd conduction, etc, etc. I imagine that there will be future Nobel prizes given out for research in this area (I believe one already has been, a few years back). Studying how superfluids act can give us some very interesting insights into what actually happens in various media at tiny sizes. One example would be looking at fluid/solid interfaces, and trying to determine what precisely goes on there. The possibilities are endless...
That being said, isn't the official definition of a fluid "something that deforms continuously under shear stress"? As such, does this indicate that these supersolids do NOT flow continuously?
"Don't bother me with that pocket calculator stuff" - Deep Thought
No actually, this does have something to do with Bose-Einstein Condensation. Now, IANATheoretical Physicist, but as I understand it, at the quantum level these results may be a manifestation of b-e condenstation in the solid phase (to date, b-e condensation has only been observed in the liquid and gas phases). Now, the original poster was a little bit out to lunch with respect to his description of what a b-e condensate is, do I still highly reccomend reading the wikipedia article. There's still a lot of work to be done before we really figure out exactly what's going on in this experiment, but it looks to have some pretty cool implications at the moment.
"Perhaps a condensed matter physicist can dumb the article down for layfolk such as myself?"
Imagine a big block of swiss cheese (the kind of cheese that's got all the holes in it). Now those holes are basically "vacancies" of cheese. Now, imagine if the holes moved around.
Similarly, think of one of those pictures underwater videos of SCUBA divers... You know when they release a breath, and all the bubbles start moving up to the surface of the water... Those are likes 'holes' in the water. More specifically, they are "vacancies" and they move in a somewhat orderly manner (up). Of course, it makes more common sense that vacancies would move around in a liquid than in solids....
So, basically, they've found a state of matter where the vacancies move around in a solid. In a sense, they're claiming that they found a block of cheese in the refridgerator where the holes keep moving. And this is why there's going to be controversy over this claim: they're alot of people who are going to say "no way - cheese doesn't work that way..."
It would make for a crazy club sandwich... Yum.
FYI: I'm not a condenced matter physicist, although I do happen to have a degree in the History and Philosophy of Science...
Any solid will flow. There are various mechanisms for this, but people usually refer to diffusion. Given sufficient time and temperature you can see any solid flow, and it doesn't have to melt into a liquid state for this to happen. The big thing here is that this supersolid is not liquid and that's because it retains a crystalline structure. Unlike a liquid, supersolid He has a structure that is ordered.
Well no actually. Higher viscosity oils are better for engines. Imagine two metal surfaces pushing into each other. You want something that isn't immediately dissipated.
You obviously did not read any of the 3 articles I linked to.
Plate glass used to be made by dipping a tube into molten glass (1000 degrees Fahrenheit or so), gathering up a blob, blowing that blob into a bubble, poking a hole in the bubble, and spinning the tube so that the bubble's hole opens up. Done correctly it makes a flat circle of glass with the end of the tube in the center. This glass is relatively even in thickness but it is still thicker in the middle then at the sides.
They let the glass cool and then cut it into squares with one side closer to the middle. This side is thicker than the rest of the piece and was usually placed toward the bottom of the window because it was reasoned that the heaviest part and strongest part should be at the base. It was not until the Float Glass process was invented in 1959 that truly flat glass was available. Up until then there would almost always be some parts of plate glass that were thicker or wavy, giving rise to the flowing glass myth.
Sapere aude!
There is a cool thermal acoustic refrigeration technique that employs hemholtz principals described in American Scientist a few moons ago. There is also a means of using a Hemholtz filter to create a kind of check valve (I have to look for that reference... if you need it ask) hence providing a "one-way" flow.
What's the big friggin deal? I've been using this stuff in the flux capacitor of my DeLorean for like twenty years...
~Doc
Helmholtz was born on 8/31/1821 in Potsdam, Germany. He ended his breathing on 9/8/1894 in Berlin, Germany.
Hence, he could not have been a Nazi...
PS, some info Helmholtz .
One of the big problems our power grid has is that electricity must be generated based on demand. There's no way to store electricity for use later during peak hours.
However, a fluid or solid that "once stirred would continue swirling forever" sounds like an interesting possibility for a storage device. Imagine causing the fluid to begin spinning at a high rate using electromagnetic fields. Then, at some later time (i.e., peak demand periods), converting the kinetic energy of the fluid back into electricity. In a sense, it's a frictionless gyro that acts as a kinetic battery.
...expect to see the next generation of Apple PowerBooks constructed from Helium-4, "the world's strongest metal".
You can see a nice small movie of actual 3He crystal growth at Leiden University.
Although supersolid He4 does not seem like a solid, by some definitions it is. At any given instant, the atoms in the material appear to be in a crystalline lattice (not bouncing around like the atoms in a liquid). But if you exert any force on that supersolid, the vacancies and defects in the lattice instantly shift to let the solid move. This gives the "solid" a shear strength of zero even if the atoms seem like they are arranged in what appears to be a rigid crystal structure.
The problem with commonsense notions of "solid" vs. "liquid" is that they don't reflect all the possible states of matter, only the ones that occur at room temperatures. Science usually finds these counterintuitive phenomena outside the usual conditions of everyday life (like when physicists proved that Newton's centuries old laws only work for "slow" speeds, so we need Eistein's equations to understand higher speeds).
Two wrongs don't make a right, but three lefts do.
If something can flow then its liquid NOT a solid. I'm not arguing the physics, I'm arguing the definition of the english words.
If something swims in the water and has fins, then it's a fish, not a mammal. I'm not arguing the biology, I'm arguing the definition of English words.
Suppose you have a metal. This has positive nucleii, bound electrons which screen most of the nuclear charge, and conduction band electrons which can move thorughout the lattice, but also help to screen the nuclear charge. The whole thing is electrically neutral.
Suppose then you have some cloud of negative charge. This charge will repel the local electrons, and will attract the local nucleii. The nuclear lattice will bend a bit towards the center of the charge cloud, generating a local region of increased positive charge density that is screened out by the cloud of charge, and the other electrons.
Now, suppose this charge cloud moves. You have the same attractions and repulsions, but the nucleii have more mass per unit charge than the electrons in the cloud, so they will take a bit of time to react. The induced positive charge region will then lag behind the negative cloud, and will tend to drag it back. If you had a second negative cloud following some way behind the first one, it might be attracted towards this positive region.
If you had two conduction band electrons with long deBroglie wavelengths, with the same sorts of velocities and at the right distance apart, then you can get this sort of action. Over a limited range, you can get electrons to apparently attract each other, via electron-phonon iteraction.
This pairing up of electrons is pretty weak. If this was the only thing holding them together then you would not get superconductivity in ordinary materials above a few millikelvin. However, one they start organizing like that, then they can all tend towards a lowest energy state, where they are all moving like a single enormous particle, with a wavelength that is so much larger than most of the usual things that scatter electrons. A more electrons join this single state, an energy gap opens up betweeen the electrons that are in the state, and the ones that aren't, and it becomes more energetically tempting for other electrons to go with the flow. This energy gap stabilizes the superelectron state, and lets superconductivity happen at kelvin rather than millikelvin.
We have lots of particles giving off heat, but it isn't solidification. We don't have electrons standing shoulder to shoulder like soldiers. One superelectron's wave will significantly overlap hundreds or thousands of other superelectrons. If they had rigid orientations, then a supercurrent could not flow down a wire that got thinner, any more than your cheese with holes in it could flow down a funnel. Also, the electron-phonon coupling only binds if the electrons move. So, forget marching soldiers, unless you have soldiers that can see what is happening a hundred ranks ahead, and automatically calculate a path that will give zero jostling with their neighbours. It is not really a state that exist in the macroscopic world, but you can sort of guess what it might be like: everyone been cool and mellow and getting along with their neighbour, until one guy borrows the lawnmower without asking, or drinks the last beer in the fridge, and then it all suddenly collapses.
Okay, now if I get the article, you can get the same sort of thing with holes in a superfluid. The helium atoms can form a similar cooperating superfluid. The forces that balance to keep the atoms flowing in a coordianted fashion are different, but the principle is the same. If the particules are moving, and enough of their fields overlap, then there will be a lowest energy state, and one enough of them have discovered it, and particles can find it faster than random thermal fluctions can chuck them out, then everhting moves smoothly.
Helium atoms as lots of little round fuzzy things. Normally they overlap with lots of their neighbours. As you squish two of them together, the repulsive nuclear forces starts to rise sharply. The strong repulsive forces from the nearest neighbours will be bigger than the others, and wil
The apparent healing of the crack that you witness is not due to flow of the material, but rather chemical attack. When you score the glass you get 2 free surfaces with unsatified bonds. These bonds are rapidly satisfied by atmospheric molecules; mostly, water or hydroxyls. These molecules have a corrosive effect of the glass surface. Over time, the once atomically sharp crack-tip is blunted by this corrosion mechanism and the glass is effectively strengthened.