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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

#171

Post by uyhgr »

Laforet wrote: post #135
uyhgr wrote: post #108

Earlier quoted context omitted.

The term is “flux pinning”, and it only applies to the “quantum lock” effect. That is the specifically static hovering effect. The diamagnetism, importantly this means repulsion of both poles simultaneously and equally (this is how you can have these magnets spin, a regular magnet repels same poles and attracts opposites, diamagnets repel both poles), is simply a characteristic of the superconductor, but it alone wou…

Flux pinning of a superconductor should be able to hold it steady below a magnet, and the magnet should be able to drag the superconductor with it when moving (within reasonable weight limits of course). These will demonstrate for sure that levitation is not simply a force equilibrium between gravity, magnetic repulsion and one corner of the material resting on the surface. There is a video from the Korean team showi…

Correct, the imperfections of the crystal allowing the flux pinning permits even a “hanging levitation”. Here is a timestamped video showing that:

https://m.youtube.com/watch?v=Ws6AAhTw7RA&t=90

If we develop methods of creating these superconductors with perfect crystal composition then there will only be the repulsion, allowing for levitation in a bowl shaped superconductor, but this “hanging levitation” would be impossible.

Perhaps we will develop manufacturing techniques to induce specific imperfections into the material to ensure predictable flux pinning; it seems like a useful, and wildly interesting side effect.

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

#172

Post by alephnerd »

hyperman1 wrote: post #137
adolph wrote: post #115

Earlier quoted context omitted.

> due to various impurities and that it will take a while before we have a sample that is pure enough that all of these properties can be nailed down for good. Do you think it will be "purity" or understanding material variance/specific impurity? It reminds me of Fogbank, the nuke material claimed to be "so secret they forgot how to make it." Part of the story of manufacturing difficulty was due to increased purity o…

It reminds me of Max Gergel's Isopropyl bromide book: When Hildebrand ran the baths the silver came out bright, and stuck to the objects; the minute he left troubles started. No one knew why. Shortly before he left to go into the antique business in Charleston he showed me the secret. It was his chewing tobacco, spat into the bath from time to time. From then on, one man in each shift chewed, and the problem was solv…

What's the name of this book? It sounds really cool!

Any other recommendations on books about the history of MatSE/Chemistry?

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

#173

Post by freitzkriesler2 »

modeless wrote: post #121

To me this is encouraging. 110K is really high! It's higher than YBCO which is what they make commercial "high temperature" superconducting tape out of. IMO if this is legit (I have no way of judging the source) then this is the first good third party evidence that the original researchers are not just doing some kind of fraud. A total fraud wouldn't have actually discovered a novel high-temperature, but not room tem…

What's impressive to me is how simple making it is. There are still low hanging scientific discoveries that are out there but that we haven't figured out yet.

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

#174

Post by uyhgr »

adolph wrote: post #132
uyhgr wrote: post #108

Earlier quoted context omitted.

The term is “flux pinning”, and it only applies to the “quantum lock” effect. That is the specifically static hovering effect. The diamagnetism, importantly this means repulsion of both poles simultaneously and equally (this is how you can have these magnets spin, a regular magnet repels same poles and attracts opposites, diamagnets repel both poles), is simply a characteristic of the superconductor, but it alone wou…

When NileRed puts the YBCO on top of the row of bar magnets and it ping-pongs back and forth is awesome! Timestamp: https://youtu.be/RS7gyZJg5nc?t=2496

The best thing about the NileRed superconductor video is it shows him initially failing to reproduce a YBCO superconductor after having already succeeded once before!

It goes to show how difficult manufacture, or in the case of the LK-99 news cycle “reproduction”, of these materials really is, and YBCO was a well documented area of superconductor manufacture.

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

#175

Post by baq »

pokey00 wrote: post #71
valine wrote: post #35

Earlier quoted context omitted.

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.

A sudden discontinuity like that but continuing the same curve and jumping back... that's equipment malfunction 99% of the time.

Why publish this graph without running the measurements again though? Serious question since I’ve no idea about the effort needed to get this data.

I’ve got a small hope that they actually did and found the effect didn’t go away. They’ll still say ’equipment malfunction’, there isn’t any downside, only upside if it gets reproduced somewhere else.

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

#176

Post by kulahan »

spandrew wrote: post #157
modeless wrote: post #121

To me this is encouraging. 110K is really high! It's higher than YBCO which is what they make commercial "high temperature" superconducting tape out of. IMO if this is legit (I have no way of judging the source) then this is the first good third party evidence that the original researchers are not just doing some kind of fraud. A total fraud wouldn't have actually discovered a novel high-temperature, but not room tem…

The initial claim was speculated to be room temp and ambient pressure superconduction. 110K is a far cry from that.

That could still be possible. We haven't found the ideal form of LK-99 yet, so another lab might have a form which is only stable to 110K, but that doesn't mean all will see the same thing.

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

#177

Post by progrus »

baq wrote: post #17
zootreeves wrote: post #10

Why would other teams be observing floating at room temp? Is it possible to have a diamagnet that becomes a superconductor?

It’s possible there are tiny bits of superconducting stuff at room temperature which connect into bigger and bigger bits as temperature drops, until it starts working as a whole at 110K. Maybe. Don’t quote me.

Due to how these materials behave, this likely means you can manufacture a real-deal UFO in orbit…

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

#178

Post by d1str0 »

carabiner wrote: post #169
saberdancer wrote: post #131

Huge news. This means it is not a scam as a discovery of this type of superconductor would be big enough. It also means it is unlikely they were measuring wrong for multiple years. My layman take is that Korean sample is just a better or different batch that is properly superconducting at room temperature.

As a layman, how do you know this is huge?

Assuming they discovered a low cost, room temperature, room pressure, superconductor, there are many HUGE technological advancements that can be made that would impact your daily life.

Possibilities include improved battery longevity in all devices(probably in an order of magnitude), low friction transport improvements (ie. cheaper high speed rail), and faster and higher bandwidth wired connections.

https://en.wikipedia.org/wiki/Technological_applications_of_...

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

#179

Post by baq »

hatsunearu wrote: post #103

The Fig 3a)b) graphs are not showing superconductivity. That just looks like the resistance dips below the ~1e-5 mark and goes goes deep into the noise. That just looks like a normal conductor that has a positive temperature coefficient. edit: to add speculation, I think they made something that's not quite LK-99, and it's behaving like a normal conductor with no superconductance.

What would be the acceptable noise floor here?

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

#180

Post by grandpa »

alephnerd wrote: post #172
hyperman1 wrote: post #137

Earlier quoted context omitted.

It reminds me of Max Gergel's Isopropyl bromide book: When Hildebrand ran the baths the silver came out bright, and stuck to the objects; the minute he left troubles started. No one knew why. Shortly before he left to go into the antique business in Charleston he showed me the secret. It was his chewing tobacco, spat into the bath from time to time. From then on, one man in each shift chewed, and the problem was solv…

What's the name of this book? It sounds really cool! Any other recommendations on books about the history of MatSE/Chemistry?

The title is "Excuse me sir, would you like to buy a kilo of isopropyl bromide?"

https://archive.org/details/gergel_isopropyl_bromide

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