41–50 of 269 posts
Doesn't it seem like there should be some sort of annealing process required? this material being essentially a powder smashed into a tablet form seems like it would likely be a very poor conductor unless the superconducting properties not only existed in each of the granules of the powder, but also can easily transition between each of the boundaries. So wouldn't you want the final thing to be closer to like a ceram…
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Some days I wish I could just run DFT on everything and have it spit out the ones with "interesting" results and then patent those. Unfortunately, this is not feasible (computationally) nor likely to produce very many true positives. I wonder if you could troll theorists into doing simulations of just about any substance by publishing convincing-looking papers in arxiv. Scratch that: we know it's possible.
You think it's over? Or are we back?
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because they just got a few mm^3, not done experimenting with it, and was not ready to publish?
> because they just got a few mm^3 But why? The base materials are cheap and easily available, and the synthesis process seems rather straightforward. Why don't they have kilograms of this stuff by now?
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From what I have gathered reading things online, there is some theorizing that given a "perfect" baking process there is something probabilistic going on that means your batch is never 100%. disclaimer not a physicist or chemist
I'm not a material scientist, but I've spoken with folks who do advanced vapor deposition and thin-film synthesis for high-temperature superconductors (the ones that work at liquid-nitrogen temperature). It's basically witchcraft-adjacent, with so many variables that getting everything right is an art. That's why we're only now getting practical high-TC superconducting tape, even though the original materials were di…
It's not quite like asking somebody with a hammer and chisel to produce a microchip, but depending on how many processes and sensitive variables affect your chemical processes, it ain't far off.
Maybes it's cooling rate. Maybe it's venting phosphorous gas. Maybe it's introducing ambient air. Maybe oxygen would be better. Maybe it should be faster. Maybe it should be introduced slower with faster cooling. Or slower cooling. Maybe the oven heats funny and placement matters given the distribution and the heating is the key.
Experimental chemistry can be a real pain, and it takes quite a lot to figure out what you've got.
> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. Unless we assume the original paper's authors were straight up lying, it sounds like this paper's author didn't end up with exactly the same material?
The original authors have apparently said they are only able to successfully produce the material in around 1 in 10 attempts and they don't yet know why. Also, replicators have reported that the information in the papers and the patent aren't entirely clear on some potentially significant implementation details. Unfortunately, real science makes for a pretty lousy spectator sport :-). Given the context of the release…
I’ve found this whole thing incredibly entertaining and informative.
> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. Unless we assume the original paper's authors were straight up lying, it sounds like this paper's author didn't end up with exactly the same material?
They mention the possibility of a mistake when measuring resistivity, which has already been discussed. But yeah, the partial levitation is not a mistake. Their abstract suggests LK-99 is a "highly insulating diamagnet", but they are not even able to "detect any reliable diamagnetic signal" with their instruments. I'd rank the possibilities as: fraud, a different material, or some comical series of bizarre mistakes a…
The biggest question in this whole thing was, why not bring a sample to another lab for verification? Well, now we’re starting to get some reproduction attempt results anyways.
Maybe he’s worried it would fuck up his research pipeline?
Given the stark contrast in behavior between their sample and the one described in Lee et al., is this even the same material? Surely while the conductive characteristics can be explained by errors in measurement procedure, why would the behavior in a magnetic field be different? Were the original authors being dishonest? Was the replicated material different? The X-ray analysis seems to support that they are very si…
Doesn’t look like they did any annealing. Just tableting. The annealed sample was the one that levitated. Maybe that’s the issue.
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because they just got a few mm^3, not done experimenting with it, and was not ready to publish?
> because they just got a few mm^3 But why? The base materials are cheap and easily available, and the synthesis process seems rather straightforward. Why don't they have kilograms of this stuff by now?
They’ve been working on this for years. To me it looks like whatever their process is, they don’t have something that’s repeatable. So maybe a couple of small samples are all there are after 1000s of attempts doing more or less the same thing.
Earlier quoted context omitted.
The original authors have apparently said they are only able to successfully produce the material in around 1 in 10 attempts and they don't yet know why. Also, replicators have reported that the information in the papers and the patent aren't entirely clear on some potentially significant implementation details. Unfortunately, real science makes for a pretty lousy spectator sport :-). Given the context of the release…
> Unfortunately, real science makes for a pretty lousy spectator sport :-). I’ve found this whole thing incredibly entertaining and informative.