LK-99: Diamagnetc Semiconductor, Not Superconductor?

Every so often, along comes a story which, like [Fox Mulder] with his unexplained phenomena, we want to believe. EM drives and cold fusion for example would be the coolest of the cool if they worked, but sadly they crumbled when subjected to scientific inquiry outside the labs of their originators. The jury’s still out on the latest example, a claimed room-temperature superconductor, but it’s starting to seem that it might instead be a diamagnetic semiconductor.

We covered some of the story surrounding the announcement of LK-99 and subsequent reports of it levitating under magnetic fields, but today’s installment comes courtesy of a team from Beihang University in Beijing. They’ve published a paper in which they characterize their sample of LK-99, and sadly according to them it’s no superconductor.

Instead it’s a diamagnetic semiconductor, something that in itself probably bears some explanation. We’re guessing most readers will be familiar with semiconductors, but diamagnetic substances possess the property of having an external magnetic field induce an internal magnetic field in the opposite direction. This means that they will levitate in a magnetic field, but not due to the Meissner effect, the property of superconductors which causes magnetic field to flow round their outside. The Beijing team have shown by measuring the resistance of the sample that it’s not a superconductor.

So sadly it seems LK-99 isn’t the miracle it was billed as, unless there’s some special quirk in the production of the original Korean sample which didn’t make it to the other teams. We can’t help wondering why a sample from Korea wasn’t subjected to external evaluation rather than leaving the other teams to make their own. Never mind, eh!

70 thoughts on “LK-99: Diamagnetc Semiconductor, Not Superconductor?

  1. To be fair to the LK-99 is a superconducter you can’t in good faith claim to have proven it’s a “diamagnetic semiconductor” because your synthesis yielded a “non-diamagnetic semiconductor”!

      1. “Clinton’s did away with the fairness doctrine in media”

        I have no love for the Clintons but what sort of mental gymnastics are you going through to blame them for doing away with it?

        The Fairness Doctrine was used by Democrats to harass broadcasters to get them to drop conservative radio shows in the 70s. It was removed by the FCC under Bush Sr. in the late 80s and killed by the Broadcaster Freedom Act of 2009 which had 31 sponsors, all Republicans.

    1. We’ve had report from four independent labs all over the world claim its not a superconductor. How many more do we need? Even the original lab that synthesized LK99 did not have conclusive evidence and stated a “possible” superconductor. So there is that.

      1. Well it’s also caused a supply chain issue, with every lab on the planet trying to reproduce results, a major problem is the original paper is lacking important specifics so everyone is guessing when trying to cook up LK-99. Unless the original team added or did something drastically different it’s more than likely diamagnetic ( which is of course disappointing) but as with all things time will tell.

      1. I want to say that Massie taught this to Reagan in ‘84 before meeting Gorbachev in Iceland. She says it’s an old Russian proverb, but I believe she said it originally came from the Russian Othodox Church, via Proverbs?

        1. ^ idk what Larry is on about it not being a semiconductor just because it’s from a korean research lab (I can only assume he’s mixing up north and south korea or something)

  2. We should just congratulate this Korean team for democratizing such a scientific miracle around the world in an instant and soon they will publish more and even send their material to outside world for confirmation.

        1. A few did. Others have suffered damage that hasn’t been fatal … yet.

          To be fair, bad reactions have been rare. A disproportionate number of the bad reactions happened to young people, who had the least need for the vaccine.

    1. In an instant? The 99 stands for… 1999. They are full of crap and likely been using this to bilk investors for years when someone got overzealous(or decided to blw the whistle) and pushed it to the scientific world without permission. Wouldn’t call sitting on what would be the greatest scientific discovery since fire for 2 decades plus an instant.

    1. It’s extremely hard to measure resistances with microgram samples. Especially since the current density from the paper is ridiculously low: you’re talking sub-nanovolt levels.

  3. A team at the Southeast University at Nanjing has measured their sample to have zero resistance at T_c>=110K. While there is still no evidence to say that LK-99 is the miracle that the Korean researchers claim, the title “LK-99: DIAMAGNETC SEMICONDUCTOR, NOT SUPERCONDUCTOR?” is nothing but disingenuous.

    1. Take a look at superconductors.org. Room temperature superconductors have been invented/discovered, but making macroscopic samples has not been achieved. Also, they’re damaged fairly quickly by water vapor.

  4. Whatever it is, it is a remarkable material. Even if it’s not a true semiconductor, it’s going to be getting a lot more attention and is probably useful on its own.

  5. Before you dismiss cold fusion, you should read up on what has happened in the field of Low Energy Nuclear Reactions or Lattice Confinement Fusion since Pons and Fleischer first stumbled upon the phenomenon. NASA has a team working out at the Glenn research center and there are many others.

    1. There is science behind the theory of cold fusion- but Fleishemen and Pons were two chemists trying to show up another professor. They never knew what they were dealing with and never knew what to control for. Anyone in nuclear science knew right off if their data was right, they would have been dead

  6. So I’ve seen the theory that LK-99 is a superconductor but the process by which it’s made yields small patches of 1 dimensional superconductivity crystalline structures. They’re scattered throughout the material so if you were to measure resistance from one end to the other you will get a measureable result when in reality you aren’t measuring a pure semi conductor. It’s like a thousand of super highways connected with 20mph street roads, so the average is way way slower than the speed limit of one highway. If true then this article would be false and would at least need amending.

  7. The production process of LK-99 is far from documented, for starters it’s missing a proper temperature profile. The published papers have sections marked as a “range” of time at a certain temperature, which is like a bad joke. Notwithstanding whatever else they might’ve missed.
    Even then, they only managed to produce 4 samples, each with slightly different characteristics.
    It’s cool that they made their findings public for others to join in on the fun, but the paper should be titled “LK-99: What exactly is it, how does it work, and can someone help us guess how we made any of it?”.

  8. It sounds like they might be on to something. It may be Paramagnetic, and not superconductive, but it may be very close. I think this is a case of keep trying, you’ll get it.

  9. fwiw

    https://arxiv.org/abs/2307.16402

    Synthesis of possible room temperature superconductor LK-99:Pb9Cu(PO4)6O
    Kapil Kumar, N.K. Karn, V.P.S. Awana (CSIR-NPL, INDIA)

    The quest for room-temperature superconductors has been teasing scientists and physicists, since its inception in 1911 itself. Several assertions have already been made about room temperature superconductivity but were never verified or reproduced across the labs. The cuprates were the earliest high transition temperature superconductors, and it seems that copper has done the magic once again. Last week, a Korean group synthesized a Lead Apatite-based compound LK-99, showing a Tc of above 400∘K. The signatures of superconductivity in the compound are very promising, in terms of resistivity (R = 0) and diamagnetism at Tc. Although, the heat capacity (Cp) did not show the obvious transition at Tc. Inspired by the interesting claims of above room temperature superconductivity in LK-99, in this article, we report the synthesis of polycrystalline samples of LK-99, by following the same heat treatment as reported in [1,2] by the two-step precursor method. The phase is confirmed through X-ray diffraction (XRD) measurements, performed after each heat treatment. The room temperature diamagnetism is not evidenced by the levitation of a permanent magnet over the sample or vice versa. Further measurements for the confirmation of bulk superconductivity on variously synthesized samples are underway. Our results on the present LK-99 sample, being synthesized at 925∘C, as of now do not approve the appearance of bulk superconductivity at room temperature. Further studies with different heat treatments are though, yet underway.

  10. My two bits: The best outcome from all this would be a surge in curiosity where researchers consider new physical mechanisms that could lead to superconductivity, whether or not the creators of LK-99 recognized them. (By contrast, the worst outcome is ideological entrenchment without action.)

  11. FOA, the term “diamagnetic semiconductor” isn’t commonly used because it combines concepts that don’t directly correlate. Diamagnetism involves weak magnetic repulsion in response to an external magnetic field, while semiconductors are defined by their electronic properties, not magnetic behavior. Describing semiconductor magnetic properties as “paramagnetic” or “ferromagnetic” is more accurate, as diamagnetism isn’t a defining trait of semiconductors.

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