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Physicists May Be One Step Closer To Explaining High-Temp Superconductivity
sciencehabit writes For years some physicists have been hoping to crack the mystery of high-temperature superconductivity—the ability of some complex materials to carry electricity without resistance at temperatures high above absolute zero—by simulating crystals with patterns of laser light and individual atoms. Now, a team has taken—almost—the next-to-last step in such 'optical lattice' simulation by reproducing the pattern of magnetism seen in high-temperature superconductors from which the resistance-free flow of electricity emerges.
perhaps engineer some meta-materials that hold such properties at room temperature.
Doesn't even have to be room temperature. Being able to make a MRI machine using liquid nitrogen instead of helium would be a huge win.
The System is continuous. There are no scale, quantum, or relativistic effects.
Utter rubbish, laddie, quite like that image you linked to. Modern thermodynamics has no such limitations. Go look up negative temperature (hint: you might have heard of such things as lasers) for a fun, discrete, quantum thermodynamic system. Heck, Planck's black body radiation was a nice, discrete, quantum thermodynamic system. Ye might want to resort to a teacher that's been around at some point during the last century or so, next time you argue thermodynamics. Such a one might point you towards such things as Bose-Einstein or Fermi-Dirac statistics and their thermodynamic interpretation. As for relativistic effects, look up thermodynamic models white dwarves, to begin with.
The laws of thermodynamics are relevant only within a narrow range of physical phenomena, which we have gotten out of.
Conservation of energy (first law) is quite relevant at pretty much any scale that was tested so far. Entropy increase and irreversible processes (second law), same thing (although there are interesting points about it w.r.t. black holes). Third law, entropy goes to a finite (sometimes zero, sometimes not) value as temperature approaches 0K was tested with quantum systems, as those are the only ones relevant at that temperature scale (thermodynamic fluctuations drop below quantum ones).
Now, the GP has a partial point, the superconducting part of the circuit does no 'useful' work, that does not mean the rest of the circuit doesn't either. Transport is important, as anyone who ever saw a superconducting magnet knows well (those things tend to be hard to transport, too). Thermodynamics gives one an upper limit of efficiency, superconducting wires simply move the efficiency closer to the theoretical limit. Overall entropy of the system increases, even if we manage to constrain it inside the superconductor (well, on the surface, mostly).
Tcs of Superconductors have been far above liquid Nitrogen for 30 years
Yeah, in brittle ceramic form. Something other than cuprates would be nice, preferably something useful ... and not too reliant on rare earths. That's the whole point of the exercise, bloody CuO plane is weird and it's been hard to study, nevermind to make for industrial applications. So they're trying to simulate it, which is quite cool imo. Personally, I'm still betting on AFM insulator effects over Mott insulator ones, but it remains to be seen.
A "low temp" superconductor relies on liquid helium to keep it cool (approx 4K). A 'high temp" superconductor relies on liquid nitrogen to keep it cool (77K).
Liquid nitrogen is stupidly cheap - tons of places use liquid nitrogen for a lot of non-superconducting purposes including packaged food preparation, cooling, experimentation (a lot of "cryo" experiments use liquid nitrogen, including the ever popular frozen rose, frozen banana and other science demonstrations).
In fact, to get rid of a small dewar of liquid nitrogen, it's usually just dumped on the table after the demo is done creating a nice effect. A more controlled evaporation is simply leaving the lid off and letting it boil off naturally.
No one keeps stuff cool by liquifying nitrogen onsite. Instead, they just have Air Liquide and similar companies come by every week or so and top off the cryo tank. The cryo tank provides the supply of liquid nitrogen that's needed for the equipment (MRI machines use it in superconducting magnets). Most labs have it available freely as well.
Liquid helium is much more expensive. Liquid nitrogen is so cheap that having it transported and even any wastage is considered "meh". Hell, schools probably buy way more than they need simply because to make it worthwhile you end up with a huge dewar of it.