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Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

arxiv.org

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Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#211

Post by klysm »

maho wrote: post #130
sanxiyn wrote: post #35

Earlier quoted context omitted.

Cooler chips. Chips heat due to resistance, and superconductors have zero resistance (by definition). I suspect this is the company's intended application. The following quote from their patent is very suggestive if you know about semiconductor manufacturing. > In addition, various energy sources used for deposition are not limited to chemical vapor deposition (CVD) using heat, but atomic layer deposition (ALD), sput…

Note that the resistance of superconductors is 0 only for DC currents. The AC resistance is not 0 and typically gets larger for higher frequencies!

I think this terminology is really confusing for people not familiar with digital electronics. The term AC to a layman usually means a single sine wave like mains. The point is though that when square waves get really fast, they have a lot of high frequency content.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#212

Post by beowulfey »

Knee_Pain wrote: post #201
beowulfey wrote: post #194

Earlier quoted context omitted.

Congratulations on owning an iPhone! (I do too, they’re great.) But I want to emphasize that the quality of the phone camera was not the point of that story.

Then what was the point? If I saw a unicorn and took out my phone in a hurry I could get a video of exceptional quality, granted I uploaded it somewhere without too much compression. Seems like you wanted to create a little abstract story ignoring the reality of hardware

Wow, I’ve never thought about it like that before. You’ve done a good job explaining your opinion on this matter! Thanks for the feedback.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#213

Post by nemo44x »

Interesting see Asian scientists working together on this. Grinding it out over years - doing the work.

Meanwhile in Europe and America they sit in their expensive “centers” and “institutes” and ask for hundreds of millions more for their experiments which have resulted in incremental at best results. And that some had the gaul to mock the Korean scientists and their poor grammar and amateur labs.

And now the West will iterate on the breakthrough. The opposite of how it has been.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#214

Post by yorwba »

ProtoAES256 wrote: post #199
yorwba wrote: post #188

Earlier quoted context omitted.

Did you understand what he said when he explained what kind of magnet he used? Different versions produced by targum claim either "aluminum shed magnet" https://targum.video/v/2023/8/1/e2ad3b8e86961ccfdcf411d2d4d1... or "cast iron shed magnet" https://targum.video/v/2023/8/1/2534a4408ccce9c13a811e94f16d...

钕铁硼磁铁，Neodymium magnet Slight chance that might be wrong, their northern accent is too strong.

Thanks, that makes sense from context. It sounded to me like the first syllable was rú, which got me wondering whether 铷 rubidium magnets are a thing... I found a patent for a "rubidium iron boron permanent magnet" https://patents.google.com/patent/CN102832038A/en but I guess that 铷铁硼 is a typo for 钕铁硼.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#215

Post by codedokode »

geuis wrote: post #191
est wrote: post #23

https://www.bilibili.com/video/BV14p4y1V7kS/ Latest update: the diamagnetism has been confirmed from a tiny LK-99 replica sample. The Author posted: > Under the guidance of Professor Haixin Chang, postdoctor Hao Wu and PhD student Li Yang from the School of Materials Science and Technology of Huazhong University of Science and Technology successfully for the first time verified the LK-99 crystal that can be magnetica…

How anyone can see anything in the video is beyond me. Just dozens of comments literally flying across the video.

This style of displaying comments looks pretty funny.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#216

Post by appplication »

peteradio wrote: post #203
jboggan wrote: post #184

Preprint by Griffin from Livermore Labs gives a theoretical explanation of LK-99's superconductivity and also explains why labs are having a hard time synthesizing it. There are two Pb sites in the crystal structure that Cu can substitute at, the lower energy one does nothing but it's the higher energy site that creates superconductivity. https://arxiv.org/pdf/2307.16892.pdf "Finally, the calculations presented here…

What does this mean for synthesis? You just have to try a ton of times and get lucky? Is there some way to influence site substitution?

I was a chemistry major, but didn’t take it up as a career so I won’t pretend to be an expert. There are a lot of tools in the chemist’s cookbook for dealing with exactly this sort of problem. It doesn’t mean it’s easy, but experienced chemists will understand how to approach solving this.

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#217

Post by [deleted] »

regularfry wrote: post #163
martyvis wrote: post #151

Earlier quoted context omitted.

Power dissipation in chips isn't an issue with the DC power supply but switching the current billions of times a second.

I thought that was the switching loss of the transistors themselves, not the interconnects?

[deleted]

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#218

Post by __alexs »

sigmoid10 wrote: post #102
__alexs wrote: post #98

Earlier quoted context omitted.

> The problem here are the normal (usually copper) wires between transistors that cause heat to build up whenever current flows through them. IIRC with the high frequencies of modern processors switching losses tend to be a larger factor than resistive losses. If you can remove the resistive losses that leaves you with a greater heat budget from switching losses which might help drive up frequency even more.

Switch losses are also resistance losses, they just get amplified by things like the skin effect.

If you have a room temperature superconductor, does that mean you can make a superconducting transistor from it?

Re: Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2

#220

Post by jcims »

jiggawatts wrote: post #87
est wrote: post #23

https://www.bilibili.com/video/BV14p4y1V7kS/ Latest update: the diamagnetism has been confirmed from a tiny LK-99 replica sample. The Author posted: > Under the guidance of Professor Haixin Chang, postdoctor Hao Wu and PhD student Li Yang from the School of Materials Science and Technology of Huazhong University of Science and Technology successfully for the first time verified the LK-99 crystal that can be magnetica…

Doesn't anyone working in the physical sciences know how to record a decent video that isn't shaky, blurry, out-of-focus, or a handheld mobile phone recording of a computer screen? He's using a digital microsocope! Just press the "record" button and upload that! I can't wait for someone to successfully reproduce it, use a polaroid camera to take the photo, print it out, fax it, and have someone scan in the photocopy,…

Keep in mind these folks probably haven't slept or taken a shower in a week. I can't imagine the intensity of making a legitimate replication attempt.
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