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by kappi 1041 days ago
https://twitter.com/floates0x/status/1688727233521979392 NEW and IMPORTANT : Study performed at Lanzhou University heavily indicate that successful synthesis of the LK-99 superconductor requires annealing in an oxygen atmosphere. They are suggesting that the final synthesis occurs in an oxygen atmosphere rather than in vacuum.

The original three author LK99 paper and nearly every subsequent attempt at replication involved annealing in the suggested vacuum of 10^-3 torr.

This paper indicates that the superconductivity aspects of the material are greatly enhanced if heated in normal atmosphere.

Authors are Kun Tao, Rongrong Chen, Lei Yang, Jin Gao, Desheng Xue and Chenglong Jia, all from aforementioned Lanzhou University

Paper is available here: https://arxiv.org/abs/2308.03218

2 comments

This seems super interesting, waiting to see if this sparks another round of fabrication attempts!
Oh man, “fabrication” isn’t a word I’d use :)

I had to reread that a couple times before I realized you meant “make” and not “fake” (…right?)

"Fabricate" is a bit of a contronym really. Like oversight or sanction. Two meanings that are almost the opposite of each other.
One that got me recently was “resign”. I don’t know if it’s an American/UK thing or what, but I read a headline that said “Footballer Resigns” and it was about the player extending his contract, not quitting his job.

I would personally hyphenate that as “re-sign” if I were talking about signatures on contracts.

I would say the meaning is always the same, the difference is what was being fabricated. Fabricated material good, fabricated evidence bad.
It’s like halfway between a true contranym and just a change of the verb’s object.

Like, you could say that Victor Ninov fabricated Element 118 in 1999, and also say that Element 118 was fabricated by scientists in 2002.

Both true statements! But of course I made sure to word them that way. You’re much clearer by inserting “evidence” in your sentence, thus saying that it was the data that was created, not the thing.

yes poor choice of words - I am one of those who wants to believe! - definitely meant "make" :)
why would this be the case? (not a chemist, but was trained in physics)
According to the screenshot attached to the tweet, it seems that the material needs to have oxygen atoms in exactly the right locations, too, not just copper. Annealing in an oxygen-deprived environment might not be conducive to that.

The original two papers were inconsistent with respect to the vacuum required in the process. Perhaps they were working with crappy equipment that can't maintain a vacuum and accidentally annealed their sample in normal atmosphere, giving rise to unusual properties. Kinda explains why even the original authors don't have enough good samples.

Wasn't the original paper's sample a result from a broken vacuum tube? Correct me if I'm misremembering.