Ambient Temperature and Pressure Superconductor

Possibly everyone already knows and waits for confirmation. That's too good to be true, so the only thing one can do is to wait and see.

Best regards, Piotr

I had to laugh out loud about the idea that people here would want to wait until all the facts are in to discuss something like this. The EEVBlog group are running wild over this one. It hasn't reached the extent the Titan submersible did, but I think it might get there.

But, I agree, you are totally right. There's no real point in trying to reach any conclusions about the veracity of the claim of superconductivity. I would like to hear from anyone who actually knows what all the data means. It appears there is the crap video (which is never claimed to prove anything, really), but even the data in the paper has some issues. I just don't know how bad the issues are.

Can you post a link to the paper in English? All I got at that site was a blue flying saucer and an error message in Korean that I can't read.

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Extra ordinary claims require a better standard of proof and all bets are off until at least one other group can verify the initial results.

A hexagonal lattice structure might work with the right dopants, but it would be a lot more reassuring if it showed superconducting behaviour when cooled down.

I remember the cold fusion debacle when you couldn't buy palladium foil or heavy water for months afterwards since everybody and their dog had a try at replicating that experiment. Some are *still* trying even now!

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I have a fun demo on my lab shelf. It’s a 1-cm square by 0.5 mm piece of nondescript black material, suspended over four NdFeB magnets arranged in a quadrupole.

When visitors come, I put it somewhere obvious, and arrange to mention casually that I came up with this interesting material when I was at IBM Research.

I can tell how much physics the visitor knows by the size of the double-take. ;)

(It’s actually pyrolytic graphite, which is hugely diamagnetic—I bought it long ago.)

Cheers

Phil Hobbs

I don't follow what you are trying to say. This material is supposed to be superconducting at room temperature. Why would you need to cool it to test it?

A problem with many 'high temperature' superconductors is that they support only small current densities (without loosing superconductivity) making them economically or even technically unusable for long power cables or electric motors.

If this LK-99 is really a room temperature superconductor, lets hope that it supports high current densities without loosing superconductivity, so that continent long power cables can be made. This would solve a lot of problems with renewable energy.

Seems we have the first verification.

In general terms superconductors invariably work better when cooled so for a room temperature superconductor you shouldn't need to cool it very much to see it really work well. I'd happily settle for one that only required mild refridgeration and was a ductile metal.

Another alternative is that it does exactly what it claims but the Earth's magnetic field is sufficient to prevent it from superconducting!

I suspect this is one destined for "The journal of Irreproducible Results" assuming here that it survives peer review to get that far.

There was a great demo with the early inefficient LEDs of dunking them into LN2 which stiffens up the lattice improves QE and decreases resistive losses the change in brightness is huge. You can't do it very often before the device croaks but it is a good one whilst it lasts.

Now modern LEDs are stupid efficient and tend to be plenty bright at

100s of uA but a lotta consumer manufacturers seem to like to set the forward current at 10 mA like a textbook from the 1980s says, anyway, and make you get out the black tape to tone it down

Please define your use of the term, "works better".

This superconductor is claimed to work above 100°C, so 20°C *is* cooled. How much cooling is required?

Based on what exactly?

As I understand it the critical current, critical temperature, and enthalpy of the material are a bit of a three-legged stool, but the CC and CT aren't totally tangential so I would think a material with a higher critical temperature would tend to have a higher critical current, all else being equal

I must try that. I have some pyrolytic graphite, also from a very long time ago, although I never noticed a diamagnetic effect when I was fixing samarium cobalt magnets to it for a medical application. (I also developed a way of electroplating gold onto it in such a way that it would not come off.) My magnetic breakaway connector pre-dated the one patented by apple by many years. John

Also low magnetic fields before they stop superconducting. The flip side is that, for Josephson junction switches, that's ideal behavior. There have been CPUs made with such superconducting materials

Able to tolerate more ambient magnetic field before it stops superconducting. Attempts to reproduce their material seem to have failed at all the sites that have tried so far. That isn't good.

Lots of claims but non-one seems to be able to reproduce their results and even they don't seem very clear on what it is they are claiming either. Anyone can fake a Youtube video.

I found one of their papers on arXiv. I don't recognise the house style of any reputable physics journal. It looks more like a press release put together by an intern having a bad day. Even allowing for English not being their first language it is pretty close to word salad with some random and badly drawn graphs thrown in which hide important details.

This is the URL of the paper I found (there are others). I could only be bothered reading one of them since they are tedious in the extreme.

This makes me a bit suspicious (although it could be an innocent mistake). All but one of the listed authors do *not* own the paper.

It looks to me more a prospectus to separate the gullible and credulous from their hard earned spondulicks.

Their recipe and production method seem strange to me since it risks having sulphur impurities in the finished product, but if it works then fair enough. Purer reagents seem to give a better graph which is good.

The diamagnetic properties seem OK up to a point but may not necessarily be due to bulk superconduction. There is a distinct possibility that if it is superconducting at all then it is only along one preferred crystal axis.(see Fig 4) The authors acknowledge that themselves.

Fig 5 I particularly dislike since it is incredibly messy and the plotting of fat data points on the main graph makes checking the derived graph impossible. The latter is awkwardly x-scaled. Don't they teach anything about clear data presentation in universities these days?

Superconductivity, like pregnancy is usually all or nothing so I find it odd that the resistance comes off baseline around 40C for a small hump and then rises gradually from 60C to 80C before reaching a plateau and then a jump at about 113C (not the 126C claimed in the abstract).

It doesn't help that their 4 point measurement method of conductivity will be invalidated if the material really is a 1D superconductor since their voltage probes would have to hit the same 1D strand to give true readings.

If it does superconduct then it is only at pretty feeble currents. The sample becomes metallic with as little as 250mA flowing at 25C. I'd like to know what current it can handle at dry ice or LN2 temperatures. Fig 6(a)

It doesn't seem to tolerate ambient magnetic fields well either Fig 6(d)

I'm not going to comment on their proposed mechanism (I last did TCM 4 decades ago) but I doubt if it is any better then the rest of the paper.

I have sent a link to one of my friends who is at a lab where real superconductivity experts reside to see what they think of it (and also to ask if they have tried making this recipe and have any results).

The fact that it isn't emblazonned on the front page of a reputable scientific journal like Nature. arXiv and Wikipedia is no place to announce such a momentous discovery if that is really what it is.

I'm inclined to file it in with LENR until such time as they can demonstrate clear behaviour that I can recognise unambiguously as superconductivity. YMMV (and clearly it does)