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LK-99: Team of Southeast University observed zero resistance below 110 K

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Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#31

That's a failed repro then right? Below 110K is below -163.15 Celcius How would that compare to other superconductors?

It is and it isn't. It's at ambient pressure (which is something useful), and there is something very odd happening much higher up that needs to be explained. They say their sample purity is higher than the one the Korean team had, so that would normally lead to better yield and easier confirmation of the superconductivity. But since it does show the Meissner effect in other samples as well at room temperature there is a lot that still needs explaining before we can say it is a failed reproduction.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#32
post #20

That's a failed repro then right? Below 110K is below -163.15 Celcius How would that compare to other superconductors?

Tc = 110 K would take the #4 spot on https://en.wikipedia.org/wiki/List_of_superconductors

At atmospheric pressure, no less.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#34
post #13

Interesting. Some people are getting strong diamagnetism at RTP, and now someone is actually seeing zero resistance at a low temperature. I'd take this as mildly positive news. It would be a surprising material if it were a high Tc (only in the LN2 sense) superconductor that is also strongly diamagnetic at room temperature (though I'm not sure if that's more surprising than a RTP superconductor).

It's confusing. You'd expect both to be present or none, it is strange to have a material that is conducting and diamagnetic at room temperature and that shows super conductivity at much lower temperature. You'd expect the diamagnetism to disappear with the superconductivity.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#35

Read the graph, there is a sharp drop in resistance from 220K-250K. Its still not superconducting but it could be hinting something?

That’s what I was thinking. In the video he brushes it off as a potential equipment malfunction, but perhaps it’s the effect everyone is looking for.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#36

Certainly no expert here but if you take the original video and replications at face value it does exhibit strong diamagnetism at room temperature. Superconductors are diamagnetic due to the Meissner effect at their superconducting temperature. This would mean LK99 is a superconductor at low temperature and separately be strongly diamagnetic at room temperature (no Meissner effect if it's not super conducting). Would…

Bismuth is a strong diamagnet, and it can enter a superconducting state (at a fraction of a degree above zero), so it's not impossible. (And lots of materials are weak diamagnets and superconduct at some point.) So it wouldn't be unheard of. That said, LK-99 would definitely be an object of lots of research if it does have those properties.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#38

credibility of LK99 claims is very very high. What are the medium term practical implications for all these potential applications?

What do you mean? If it's only a superconductor below 110K, that's not nearly as significant.

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#39
post #16
post #8

Earlier quoted context omitted.

In the Resistance-Temperature graph ( https://twitter.com/Lipez400/status/1686793608626663441/phot... ) the resistance starts increasing from 110K

What’s the explanation for the sudden drop between 230K and 250K? It’s not dropping to zero but something is happening there.

perhaps it's an imperfect synthesis?

Re: LK-99: Team of Southeast University observed zero resistance below 110 K

#40
post #16

Earlier quoted context omitted.

What’s the explanation for the sudden drop between 230K and 250K? It’s not dropping to zero but something is happening there.

Yes, very odd. This may be why the original team believes they have a superconductor on their hands, but it doesn't quite get there and yet it does show the Meissner effect so something doesn't quite add up yet.

Original team had 20 years to play the synthesis lottery. Maybe you tweak the setting just enough and that low resistance drops to zero. Who knows, I’m still feeling optimistic.

He said in the video that their sample was more pure than the original paper. Would be wild if some impurity is what pushes it over the edge to a full blown super conductor.

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