Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism · HackerPapers discussions

Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by hgrbrm

Wed, 09 Aug 2023 17:06:44 GMT

They measured the resistivity of a pure Cu2S sample, a sample S1 containing 95% LK-99 and 5% Cu, and a sample S2 containing 30% LK-99 and 70% Cu2S. The resistivity of the Cu2S sample has a drop of 3 to 4 orders of magnitude at about 390K (when temperature decreases). In the S2 sample the drop is much smaller, only factor 5. In S1 there is no such drop. Here the resistivity always falls with increasing temperature. Then they write in the conclusion: "The superconducting-like behavior in LK-99 most likely originates from a magnitude reduction in resistivity caused by the first-order structural…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by lifthrasiir

Tue, 08 Aug 2023 04:21:34 GMT

These are just how they wrote their own names in arXiv papers [1]. I don't know about Young-Wan Kwon, but Hyun-Tak Kim is a research professor in US university and should have settled on that matter. After all I'm also Korean and I prefer my name to be written as "Kang Seonghoon" (i.e. the surname first), but I often go pragmatic and use "Seonghoon Kang" instead in order to be consistent with others. I'm very much aware of this issue. [1] https://arxiv.org/abs/2307.12008 and https://arxiv.org/abs/2307.12037

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by hgrbrm

Fri, 04 Aug 2023 07:23:23 GMT

How do you explain the almost three orders of magnitude drop in resistance in Fig. 6d in one of the original articles ( https://arxiv.org/pdf/2307.12037.pdf ) with a few LK-99 particles sprinkled here an there? There must be a current path along which more than 99.8% of the material is in the supposed superconducting state. So the particles almost touch but not quite yet? I think the more likely explanation is that the particles do touch each other but the interface is not superconductive. In other words, it is a polycrystalline material, and most of it is LK-99, but the grain boundaries are…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by floxy

Tue, 01 Aug 2023 20:46:52 GMT

The original paper dropped July 22nd: https://arxiv.org/abs/2307.12037

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by floxy

Tue, 01 Aug 2023 20:41:38 GMT

>There has only been one weekday since the LK-99 revelation The original paper drop was July 22nd. https://arxiv.org/abs/2307.12037

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by joefigura

Tue, 01 Aug 2023 06:43:27 GMT

I just wrote a comment in another thread that's relevant here too. It looks like the first superconductor paper was released by a rouge researcher, without the agreement of the other two authors or the rest of the LK-99 group. This forced the LK-99 group to rush to publish the official paper, with a cost to quality. The LK-99 group released v2 a week later (on Saturday), and probably will continue to update it. A premature release explains many of the oddities about the two papers The first paper submitted is titled "The First Room-Temperature Ambient-Pressure Superconductor." It lists three…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by joefigura

Tue, 01 Aug 2023 06:39:16 GMT

This comment intrigued me, so I pulled together some information. The first paper submitted is titled "The First Room-Temperature Ambient-Pressure Superconductor." It lists three authors: Sukbae Lee, Ji-Hoon Kim, and Young-Wan Kwon. Its timestamp is Saturday, July 22, 2023 at 07:51:19 UTC. [1] The second paper submitted is titled "Superconductor Pb10−xCux(PO4)6O showing levitation at room temperature and atmospheric pressure and mechanism." This paper lists six authors: Sukbae Lee, Jihoon Kim, Hyun-Tak Kim, Sungyeon Im, SooMin An, Keun Ho Auh [2]. Its timestamp is Saturday, July 22nd, 2023 at…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — HN submission

Tue, 01 Aug 2023 06:12:59 GMT

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

476 points; 290 discussion replies on HN. Paper and source history. A submission is not an endorsement.

Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by sanxiyn

Thu, 27 Jul 2023 00:04:35 GMT

As far as I can tell, https://arxiv.org/abs/2307.12008 is the paper by the original group and https://arxiv.org/abs/2307.12037 is the paper they wrote with an outsider. Their chosen independent outsider is Hyun-Tak Kim.

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by hgrbrm

Wed, 26 Jul 2023 23:00:01 GMT

On page 4 they list two equivalent criteria for superconductivity: "the electric field criterion with 1 μV/cm or 0.1 μV/cm and resistivity criterion with 10^-11 Ω·cm." On the same page they write: "In various bulk samples, specific resistance was measured in the range of 10^-6 to 10^-9 Ω·cm." That does not meet the resistivity criterion, not even close. In the second paper ( https://arxiv.org/abs/2307.12037 ) on page 8 they write: "In the first region below red-arrow C (near 60°C), equivalent to region F in the inset of Fig. 5, the resistivity with noise signals can be regarded as zero." I…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — HN submission

Wed, 26 Jul 2023 11:42:45 GMT

Superconductor Pb10−xCux(PO4)6O showing levitation at room temperature

4 points; 3 discussion replies on HN. Paper and source history. A submission is not an endorsement.

Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by botro

Tue, 25 Jul 2023 18:57:52 GMT

But they've trademarked the name KL-99 (®) in their follow-up paper: https://arxiv.org/pdf/2307.12037.pdf

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by eig

Tue, 25 Jul 2023 18:57:42 GMT

A sister paper [0] has a photo of the material exhibiting the Meisner effect and levitating over a magnet, and claims to have a video too. Either they blatantly photoshopped the photo or they actually made a room temperature super conductor. I can’t see how the could have made a subtle mistake that resulted in magnetic levitation at room temp without making a superconductor. [0] - https://arxiv.org/abs/2307.12037

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by obblekk

Tue, 25 Jul 2023 18:26:42 GMT

The method to produce this material as described in the related paper [1] is fairly simple and could be done at home with a $200 home metal melting furnace from amazon and the precursors (which also seem to be fairly standard easy to obtain metals). If this is real, I'd expect some smart people from hackaday / youtube to reproduce this within weeks if not days. If this is real, it'll change society quickly and permanently for the better. There's obvious wins in energy transportation and even generation, but actually having a room temperature superconductor is likely to result in an explosion…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by sheepscreek

Tue, 25 Jul 2023 17:22:18 GMT

One of the authors in a related paper[1] is Hyun-Tak Kim. He has many publications in peer-reviewed journals[2]. One even has > 1500 citations[3]. I can't tell if there is a catch anywhere, this seems pretty legitimate. Also, unlike some previous claims that required sophisticated setup to reproduce, this seems dead simple. I think we will hear from other researchers very soon. 1. Superconductor Pb10-xCux(PO4)6O showing levitation at room temperature and atmospheric pressure and mechanism: https://arxiv.org/pdf/2307.12037.pdf 2. Google Scholar…

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Superconductor Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O showing levitation at room temperature and atmospheric pressure and mechanism — mentioned by beanjuice

Tue, 25 Jul 2023 17:00:24 GMT

There was another in the same day [0], funny. Maybe it really did happen. [0] https://arxiv.org/abs/2307.12037

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