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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

#111

Post by TylerE »

ruined wrote: post #54
bick_nyers wrote: post #18

Earlier quoted context omitted.

Could you explain why? Sounds intriguing.

musicians often use them to generate distortion, which is purely an electrical phenomenon. germanium components tend to filter high frequencies and don't clip as sharply as silicon, generating tonal effects that can't really be replicated. but mostly, a lot of early guitar pedals used germanium components, and so they are associated with prestigious historic guitar players. here's a video demonstration. silicon first…

Also the forward operating voltage of germanium is about half of silicons (0.3V vs 0.7V)

Re: Origin of correlated isolated flat bands in LK99

#112

Post by rezonant »

jakeinspace wrote: post #40
losteric wrote: post #26

Earlier quoted context omitted.

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.

Well you can apparently make diodes with them: https://scitechdaily.com/mit-develops-superconducting-device...

Re: Origin of correlated isolated flat bands in LK99

#113

Post by j45 »

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…

I’m not an expert in anyway but when I see detailed chemical compositions in an arxiv summary, a patents, and multiple publications, it’s almost like it’s ready to smile at all the scrutiny.

Re: Origin of correlated isolated flat bands in LK99

#115

Post by yetihehe »

Culonavirus wrote: post #103
floxy wrote: post #61

Earlier quoted context omitted.

Most superconducting logic families aren't using transistors at all. They use Josephson junctions, which are just two pieces of superconductor separated by a non-supercondutor. RSFQ (Rapid Single Flux Quantum) uses millivolt-high picosecond-long pulses to represent logic 1 and their absence as logic zero, instead of using voltage level as in CMOS. https://ieeexplore.ieee.org/document/783712 (770 GHz toggle flip-flop…

Sooo, a 770 GHz processor? Do I understand it correctly? Jesus.

If using that flip-flop, whole processor will be closer to 100ghz (typically there are multiple transistors which need to stabilise before you have a result of computation). But probably those superconductors could enable even faster transistors and maybe we could get 1THz processors.

Re: Origin of correlated isolated flat bands in LK99

#116

Post by Hermitian909 »

KRAKRISMOTT wrote: post #62
ivalm wrote: post #43

Earlier quoted context omitted.

You have to put in the structure and then it's expensive to do the calculation. The space of possible structures is extremely large. If you have candidates then you can run through them, but you can't just random search through trillions of trillions of candidates.

What are all the material science ML companies doing? This would be a perfect technology demo if they can find the target

I've worked on the CS side of new material discovery.

The tricky thing is that you don't actually have that much data so ML is not even close to plug and play. If you want to get results you end up needing to pair ML with a lot of theory and some tricky algorithms to help narrow the search space and even then that space is huge.

Progress is being made but I think we're still at least 5-10 years from CS providing a real inflection in materials discovery.

Re: Origin of correlated isolated flat bands in LK99

#117

Post by petesergeant »

zanderwohl wrote: post #19
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?

It's going to be a long time before it's put into use if this paper is correct. While it's exciting that a mechanism has been discovered (possibly), it seems to imply that the current method of synthesizing it is partially luck-based, and not very high quality. Of course, if we do understand how it works, lots of people will put lots of research into making a more reliable process, but it's going to take time. I'm no…

If it’s shown it’s theoretically possible there’s going to be a gigantic reallocation of resources into productising it and figuring out to make production work. “It’s theoretically possible but hard” is a world of difference away from “unsure if theoretically possible”

Re: Origin of correlated isolated flat bands in LK99

#118

Post by vasco »

SamPatt wrote: post #63
drones wrote: post #9

Even if LK99 isn't the real deal, god has it been an exciting 2 weeks. Though I know absolutely nothing about material science, I have enjoyed the sheer enthusiasm and optimism the scientific community has shown. I feel like I'm part of something unique and special, something which could have only been achieved by the medium of accessible mass communication. The excitement here is palpable. I feel fortunate to be par…

I sometimes wonder what it would have been like to witness the emergence of fundamental new technologies, like electricity or radio. Then I remember I'm further along the tech tree than they were, and what a gift that is. It's very exciting to watch it update in real time. Now I'm envious of future generations (I think humanity has a bright future despite the current gloom groupthink).

I was many times sad to not be in the future just to get more history to read and more ahead on the tech tree as you say. One of the most interesting things in life is the "story" of life itself. I don't mind not living later but I'd really like to know what happens!

Re: Origin of correlated isolated flat bands in LK99

#119

Post by alberto_ol »

cubefox wrote: post #23

It's funny to read all those grammatical mistakes in the abstract. They are probably just not native English speakers, but to me it sounds like they were frantically typing the paper as soon as they finally got results after a 20 hour lab marathon and way too much caffeine. :D

From her wikipedia page, Sinéad Griffin is an Irish physicist, so she seems a native English speaker

https://en.wikipedia.org/wiki/Sin%C3%A9ad_Griffin

Re: Origin of correlated isolated flat bands in LK99

#120

Post by Blackthorn »

dtx1 wrote: post #60
ruined wrote: post #54

Earlier quoted context omitted.

musicians often use them to generate distortion, which is purely an electrical phenomenon. germanium components tend to filter high frequencies and don't clip as sharply as silicon, generating tonal effects that can't really be replicated. but mostly, a lot of early guitar pedals used germanium components, and so they are associated with prestigious historic guitar players. here's a video demonstration. silicon first…

> generating tonal effects that can't really be replicated. Seems my headphones can replicate it judging from hearing the audio. Am I missing something?

Well, it's the creation rather than the playback that's important, but you aren't really missing anything. It's not like the various waveshaping functionality of those aren't documented, they're entirely reproducible in software.
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