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New Form of Matter Melds Lasers, Superconductors
sterlingda writes "Physicists at the University of Pittsburgh have demonstrated a new form of matter that melds the characteristics of lasers and superconductors. The work introduces a new method of moving energy from one point to another as well as a low-energy means of producing a light beam like that from a laser. The new state is a solid filled with a collection of energy particles known as 'polaritons' that have been trapped and slowed using a technique similar to that used to produce a Bose-Einstein condensate. The work is published in the May 18 issue of Science (subscription required to read beyond the abstract)."
Again one step closer to that lightsaber. :)
Fucking Luddite. Out of my way. If they ever start selling mini black holes on ThinkGeek im first in line.
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beware he who would deny you access to information, for in his mind he dreams himself your master
Problem being, they have to do these experiments to get us off of the planet in the first place...
Good luck combining fermions with photons. Photons are very much a type of boson, which means they're very much _not_ fermions. Perhaps the biologists should just combine mitochondria and chromosomes too, you know, to simplify the math?
This business with polaritons in semiconductors sounds a lot like the way phonons in crystal lattices work.
A phonon is a sort of derived particle. It isn't a fundamental particle in itself but it represents a quantized mode of vibration in a lattice of more fundamental particles. But as a quasiparticle it exhibits the same types of behavior as other particles subject to quantum mechanics.
Their classical analogue would be standing waves in a crystal lattice. These lose part of their classical wave-like character and become more particle-like when the vibrational energy in the crystal decreases to near zero. The vibrational energy at extremely low temperatures takes the form of a few phonons bouncing around in the crystal like free particles in a hollow box. Phonons are ultimately responsible for all conduction of sound and heat through solids.
A polariton is apparently the coupling of a photon with one of these, and they're claiming to have gotten interesting collective behavior. I'm not sure if this is a "new state of matter" but we may get some cool toys out of it.
Okay, I found this other article about this discovery, and thought it was pretty good. It's worth a read:
http://physicsweb.org/articles/news/11/5/17/1
So this thing is like a BEC, but it's made of "excitons" (electron-hole pairs) plus the photons causing the excitation. But these "polaritons" are so short-lived, I'm wondering what this invention could be practically used for. They're calling it a "quasi-equilibrium" system, because it's more of a dynamic equilibrium.
Could this "polariton condensate" be used to probe "quantum foam", or spacetime, or something? They've already said it's more energy efficient than a laser.
Surely something this exotic must be able to confer on us some useful ability, that it would have some practical application -- even if only for research purposes.
When I think of an exciton-photon combination as compared to electron inversion, then it reminds me of the difference between a turbine and a piston engine. This "polariton" thingy (exciton-photon combo) would be more efficient than the laser in a way that's analogous to how the turbine is more efficient than the piston explosion. I'd think that the key to maximizing its advantage is by stimulating the excitons with the highest energy photons possible. That way you're maximizing your energy savings from this more efficient process.
Hmm... so maybe it might be useful for laser-confinement fusion after all. Maybe it could be used for laser-based rapid-manufacturing, etc.
Whatever it is, you'd probably want it for a short-range application, due to the brief lifespan of the polaritons.
Over the last ten years I've watched the news releases about physics--and it seems that physics is wh0ring itself out just for news headlines.
Perhaps you should actually read the scientific journal articles if you're serious about this, instead of reading the popular reviews which are by definition "dumbed down" such that non-PhD's can understand in layman's terms what is going on.
Did they really demonstrate a new form of matter? What did we have at one time? Solid, liquid, gas, and plasma. We could have mixtures of the forms--like a suspension was a fine mixture of a liquid with a gas.
Did you actually read the JOURNAL article, or are you just extrapolating bullshit based on a popular science review of the actual journal article? If you actually didn't think physicists were 'whoring themselves out' your post would make you look significantly less ignorant.
You quote liquids and gases as being two distinct forms of matter, yet they're actually the same if you look on a phase-diagram plot. So why do you list them as being two separate phases?
Oh wait, that's right, you can go CONTINUOUSLY from liquid to gas, without any phase transition, along a proper thermodynamic trajectory of course! What makes them look like separate states of matter is whether you have a phase transition as you alter the system. And the phase-transition line (in pressure-temperature space) actually ends in a critical point (see here , such that you can choose a proper p-T trajectory either WITH or WITHOUT the phase transition.
Would you call a superconductor a new state of matter? It certainly is quite different from the metallic state, with a well-defined phase transition as you cool below Tc. What about a Bose-Einstein Condensate? What about a phase-transition from superconducting-like nature to BEC? These have all been well studied, and all are acknowledged as states of matter.
The fact that you question whether it's a new state of matter, and you refer merely solid, liquid, gas, and plasma without any reference to phase transitions, really shows your limited understanding of this subject. And that makes it all the more humorous that you actually go on to claim physicists are whoring themselves out.
make world, not war
No, they meant with the properties of a laser [beam]. The polaritons are coherent when they're confined, just* like photons are coherent in a laser beam.
Using specially designed optical structures with nanometer-thick layers-which allow polaritons to move freely inside the solid-Snoke and his colleagues captured the polaritons in the form of a superfluid. In superfluids and in their solid counterparts, superconductors, matter consolidates to act as a single energy wave rather than as individual particles.I suppose saying "beam" or talking about the photons in the laser beam would have been slightly more clear to the people who didn't read the article, but it's hardly something poorly written enough to be complaining about.
IAA physicist and material scientist, but I don't know enough about superconductors to really make worthwhile comments on that analogy. However, I am under the impression that the electrons pair up to form bosons that are then able to occupy the same energy levels and become coherent whereas normal electrons are fermions and can't do that.
* horrible, horrible use of the word "just"Fermions spin? Half integer. Bosons spin? Full integer. Arguing about quantum physics on /.? Priceless.
Godless heathen.
Maybe quantum mechanics invites bipolar trolls. If someone claims a wave, they can argue a particle. If someone claims a particle, they can argue a wave. If some claims duality then they can argue ambiguity.
You're totally confusing spin with particle/wave duality, which makes one really wonder what the hell you are talking about. You may be impressing the moderators with your blatantly-incorrect usage of fancy techie-sounding words, but it's quite obvious to the physicists here that you have no clue what you're talking about. And the irony is that you're guilty of that 'whoring out' which you are accusing actual physicists of.
Your original quote misconstrued the nature of fermionic vs bosonic natures of quanta, which the GP clarified, and you resorted to a wikipedia quote, which is quite out of context.
Irrespective of particle-wave nature, photons are spin-1 bosons! Why the hell are you bringing particle/wave duality into the picture at all?
All I suggested is that, rather than pronouncing new unprecedented discoveries every month, maybe the physicists ought to look into solidifying their dual wave-particle of photons. They'll find that all these other "new particles" and "new forms of matter" fit neatly with a which has been established for at least fifteen years.
If you had an inkling of the physics research, including theoretical, simulational, and experimental, that goes on in "highly-correlated" condensed-matter systems, you'd understand that the framework for identifying the various quanta and behaviors are well-defined within the basic "standard model" for realizable laboratory conditions. And this has been well-understood for longer than 15 years, what exactly is this 15-year time frame you're quoting anyway?
What is interesting is how modern 'exotic' materials can exhibit quanta with different charge, spin, phonon, etc properties than 'plain vanilla' systems. See spin-charge separation in a Luttinger Liquid for an older example. Armchair scientists like you may prefer to use the recent buzzword of emergent behavior if you like, although I don't agree Laughlin's mindview on the whole field of emergence.
make world, not war
Guys, "Homeless" here *does not know what he is talking about*. Please stop modding him up. Both fermions and bosons are quantum fields (i.e. wave or particles but neither really), but their properties are vastly different for reasons that a real physicist IS taught in 1st year undergrad - The difference between spin odd-integer/2 and spin integer fields is vitally important and fundamental to physics. The ONLY KNOWN WAY to transform bosons into fermions at a fundamental level (as opposed to by mere aggregation - obviously even numbers of fermions together can act as pseudobosons, or by dimensional reduction - as in the weird fractional quantum hall effect that affects quantum systems confined to 2D) is via a "supersymmetry transformation", a so-far-only-theoretical construct.
Hi, I want to explain something here. This thing produces normal lasers, that are the same as the lasers we already know and love. The difference is that it can produce them using much less power input. The traditional method of electron population inversion requires more energy input for the amount of laser beam you get out. This new polariton method can make the same amount of laser for less energy inputted.
For laser-confinement fusion, you'd want that kind of energy savings.
Or SDI, or that ballistic missile interception laser mounted on that Boeing aircraft.
I'm even wondering if those desktop particle accelerators based on laser-wakefield effect wouldn't also benefit.
Anything that requires a high-power laser beam could benefit from this new polariton laser method. A turbine is already going round and round like a polariton, and is distinct from the discrete reciprocating motion of a piston, or the population inversion of electrons.
Okay, I know -- here's a good application:
http://www.mcp-group.com/rpt/rpttslm.html
Selective Laser Melting. It's a relatively new rapid prototyping technology which uses laser beams to melt powdered metal or plastic, so that it can be formed layer-by-layer into 3D parts.
So this would be an example of what this polariton laser would be good for, because the polaritons can generate the laser much more efficiently than conventional electron population inversion. Your power requirements would be reduced by 90%, and possibly even more.