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Origin of correlated isolated flat bands in LK99

arxiv.org

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Re: Origin of correlated isolated flat bands in LK99

#31

Post by dcow »

raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

It doesn't reproduce: https://arxiv.org/abs/2307.16802. That doesn't mean there's not something to further investigate, but LK-99, at least as described in the paper, is not it.

Re: Origin of correlated isolated flat bands in LK99

#32

Post by pengaru »

raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

Disclaimer: this is not my area of expertise in the slightest.

If we have the ability to computationally determine these things without any experimental data needed, and we know we're looking for a specific band structure, wouldn't we just do an automated search of possible chemistries to find everything producing said band structure?

Then just whittle down that list to the easiest to produce and most common materials for the first to test... what am I missing?

Re: Origin of correlated isolated flat bands in LK99

#33

Post by enraged_camel »

pengaru wrote: post #32
raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

Disclaimer: this is not my area of expertise in the slightest. If we have the ability to computationally determine these things without any experimental data needed, and we know we're looking for a specific band structure, wouldn't we just do an automated search of possible chemistries to find everything producing said band structure? Then just whittle down that list to the easiest to produce and most common material…

>> If we have the ability to computationally determine these things without any experimental data needed, and we know we're looking for a specific band structure, wouldn't we just do an automated search of possible chemistries to find everything producing said band structure?

Isn't this a plot point in that one Star Trek movie (episode?) where they go back in time and program a current-day computer to do this?

edit: OK, I misremembered. Was thinking of this: https://www.youtube.com/watch?v=LkqiDu1BQXY

Re: Origin of correlated isolated flat bands in LK99

#34

Post by cubefox »

dtx1 wrote: post #3

Even if LK99 turns out to be a dud, it's proven that there's a great need and great opportunity for more direct communication from scientist on their experiments via the internet. Live Stream of the Synthesis, Twitter Threads giving life updates of different teams, etc.

The first three author paper was uploaded by someone who wasn't authorized by the others to do so, and since that one was so flawed, the others apparently were forced to quickly upload the six author version, which was better but still flawed. So it seems the whole thing was intended to happen in a much more orderly matter than it did.

Re: Origin of correlated isolated flat bands in LK99

#35

Post by lambdasquirrel »

I wonder how one would draw out a wire made of such a material. From the sound of it, the copper atoms have to be in the exact right place in the lattice. Wouldn't naively working with the alloy ruin the superconducting properties? Maybe an actual MatSci person would know.

Re: Origin of correlated isolated flat bands in LK99

#36

Post by jacquesm »

dcow wrote: post #31
raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

It doesn't reproduce: https://arxiv.org/abs/2307.16802 . That doesn't mean there's not something to further investigate, but LK-99, at least as described in the paper, is not it.

It doesn't reproduce in that case, which is a useful data point but may not be the final word. The article linked in this thread suggests why making it may not be all that easy.

Re: Origin of correlated isolated flat bands in LK99

#37

Post by pengaru »

dcow wrote: post #31
raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

It doesn't reproduce: https://arxiv.org/abs/2307.16802 . That doesn't mean there's not something to further investigate, but LK-99, at least as described in the paper, is not it.

What the simulation is saying though is that it requires some luck, not all the arrangements result in the band structure.

Re: Origin of correlated isolated flat bands in LK99

#38

Post by jacquesm »

pengaru wrote: post #32
raziel2701 wrote: post #10

Man, I'm feeling stronger about LK-99 being it. This paper is theoretical and she finds that particular Cu substitutions onto specific Pb atomic sites are key to enabling a band structure that is usually linked to high Tc superconductors. What this means for the more practical minded is that the synthesis of superconducting LK-99 is not trivial and you need to make the appropriate substitutional alloy for this to wor…

Disclaimer: this is not my area of expertise in the slightest. If we have the ability to computationally determine these things without any experimental data needed, and we know we're looking for a specific band structure, wouldn't we just do an automated search of possible chemistries to find everything producing said band structure? Then just whittle down that list to the easiest to produce and most common material…

The parameter space for such a search even with a limited number candidate materials is immense. You'd need to guide the search somehow, that band structure might be the one, or it may not be... and every candidate that you flag will have to be synthesized which may not be all that easy.

Re: Origin of correlated isolated flat bands in LK99

#39

Post by vermilingua »

lambdasquirrel wrote: post #35

I wonder how one would draw out a wire made of such a material. From the sound of it, the copper atoms have to be in the exact right place in the lattice. Wouldn't naively working with the alloy ruin the superconducting properties? Maybe an actual MatSci person would know.

Just don't do it naively /s

Re: Origin of correlated isolated flat bands in LK99

#40

Post by jakeinspace »

losteric wrote: post #26
caesil wrote: post #7

Out of curiosity, since this seems like a real inflection point toward trending in that direction, if it becomes increasingly likely that LK-99 or similar material is indeed a high-TC superconductor, what will savvy people be positioning themselves to do? What are good investments? What companies will be started, or what will existing companies be pivoting toward?

Posting for Cunningham's law :) * Green energy suddenly becomes way more viable. Megaprojects in the most efficient sites can send energy long-distance and store it with effectively no loss, somewhat mitigating regional variations (especially if we have a high-trust world order where a united global grid is viable). (I read LK99 might have some limitations carrying lots of current but presumably other approaches woul…

Sorry, but how does one create a transistor from a superconductor? Maybe I’m missing something here.
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