Much better. I am not sure what to make of fractional quantum states however, back when I took quantum mechanics fractional states were as impossible as having electrons at mid-energy levels.
Solid materials are much more complex than single atoms and support several types of multiple particle states. One
noteworthy example is the Cooper pairs that result in conventional superconductivity. Spin-liquid states are also multi particle states with the interesting property that they exhibit entanglement between the magnetic moments of the atoms, and it is this entanglement that makes them intersting for quantum informatics because it can be used fo form qbits.
An intersting feature of the Herbertsmitihe crystals that were used for the study is that have a geometric structure that frustrates the ordering of the magnetic moments (or spins) of the atoms. The magnetic moment will try to align in opposite directions but the crystal structure has three magnetic moments in each unit cell and therefore only two of them can allign in an energetically favorable state while the last one is unable to moove into a stable equlibrium. Since there is no distinction between the three magnetic moments per se, the frustration is spread across the whole solid structure and a "large" entangled stage is formed.
Because these states are not locallized they are not constrained by the atomic properties of the cryatal atoms and therefore they are allowed to accept excitations at a continous range of engergies rather than the discrete ones that we normally see. It is a little bit similar to free electrons in metals. They can also be excited by a continous range of energies because they are free to move within the material.
An important thing to note, however, is that these experiments were carried out at 1.6 K, where thermal fluctuations play a very small role compared to room temperature. Therefore it is not likely that this effect will be portable to regular electronics devices. More likely quantum informatics applications include massive server like facilities that has the infrastructure to cool the devices down to cryogenic temperatures and the best we can hope for in terms of avaliability is some kind of cloud service.
My vary limited understanding of that was it was closer to an emergent state on a surface vs. something that ever applied to an individual atom. Can you clarify what's going on?
They aren't excitations of individual electrons, but of the system as a whole. I'd assume they're some sort of quasi-particle, though this isn't really my field.
There is a good chance that MIT's press release was written , outlined, or edited by the actual scientists who did the research. I recall working in OpenAcess publishing and we would inform the author's when their paper was published so they could time the press release.
Thanks for this. It is a lot more informative and accurate than the Extremetech article while remaining greatly more accessible than the original Nature journal paper.
In particular, the fractional quantum states/excitations aspect was completely missing in the Extremetech article.
More informative indeed, but still with the unexplained "There is no theory that describes everything that we’re seeing." What are they seeing that no theory describes?
Most things below the atomic level occur in quantized form, meaning variables that hop between discrete states. For example, energy radiated by electrons falling into a lower orbit is exactly equal to the difference in energy between the two orbits. Or take sub-atomic particles that have properties like spin, this also occurs in discrete steps. What this means in the context of these new magnets though I'm not sure. I seem to recall a paper where fractionalized spin states where hypothesized but I can't find it right now.
Interesting how often scientific research links on HN seem to be to discoveries with Chinese names in American universities. As someone who didn't study in the US, are there particularly large numbers of Chinese students and professors in say MIT?
The top physics kids in the US tend to get picked up by financial (or some other industry) firms because they're really really sharp because making 200k sounds much better than making 30k. This means that the kids who go into physics are doing it because they truly love the subject but it also means that we have a much smaller percentage of kids going into graduate studies than otherwise. This, combined with the fact that many countries are rapidly industrializing and newly able to support an academic class means that lots of international students are applying to Harvard/MIT/Stanford/etc where some of the best science in the world is happening. Some of the foreign kids go back, some stay here. It really depends. As for makeup? probably 40%-50% of my entering cohort was foreign and probably 60% of the foreigners were asian. That's not really a bad thing though. They're brilliant scientists and it's truly a pleasure to collaborate with them and everyone else in my programme as well.
Disclaimer, I'm a physics PhD student at Harvard and go to seminars a lot with kids from MIT.
