Room Temperature, Ambient Pressure Superconductivity—This Time for Real?

That calls for digging this parody out of the groove-yard of forgotten hits. What if North Korea had discovered room temperature super-conductivity?

OK, go ahead & hate me.

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Full levitation?

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Assertion: novel, but not superconductor.

Polymarket down to $.14

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Here is a paper from three authors at the Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science who prepared a sample of LK-99 according to the instructions in the original papers and tested it.

Here is the abstract:

Lee et al. reported that the compound LK99, with a chemical formula of {\rm Pb}_{10}−_x{\rm Cu}_x({\rm PO}_4)_6{\rm O} (0.9<x<1.1), exhibits room-temperature superconductivity under ambient pressure. In this study, we investigated the transport and magnetic properties of pure {\rm Cu}_2{\rm S} and LK-99 containing {\rm Cu}_2{\rm S}. We observed a sharp superconducting-like transition and a thermal hysteresis behavior in the resistivity and magnetic susceptibility. However, we did not observe zero-resistivity below the transition temperature. We argue that the so-called superconducting behavior in LK-99 is most likely due to a reduction in resistivity caused by the first order structural phase transition of {\rm Cu}_2{\rm S} at around 385 K, from the β phase at high temperature to the γ phase at low temperature.

They conclude:

In conclusion, we measured transport and magnetic properties of pure {\rm Cu}_2{\rm S} as well as the mixture LK-99/{\rm Cu}_2{\rm S}, and reproduce the experimental results of resistivity. We found a sharp drop in resistivity, however, none of them show zero-resistivity. The superconducting-like behavior in LK-99 most likely originates from a magnitude reduction in resistivity caused by the first-order structural phase transition of {\rm Cu}_2{\rm S}.

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Polymarket down to $0.08

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Would it be fair to assume that the net benefit is drawing attention to the possibility of creating low resistance materials relying on the peculiar configuration identified with LK99?

A whole industry dedicated to selectively doping semiconductor substrates emerged in the 1960s and became the underlying support for the massive industrial and technological advances made possible by microprocessors.

I imagine LK99 type materials hold a lot of potential even if it turned out it’s not a bona fide superconducting material.

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Yes… If all that comes out of this is a computer model of the materials that via gradient descent can find superconductors or even just low resistance materials we should expect to see big advances.

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We still don’t know the precise mechanism by which the cuprate high temperature superconductors work. It’s pretty clear it has something to do with constraining electrons to a near-two-dimensional structure, but the details are not understood. It seems entirely probable that by studying these materials and others, such as LK-99, that exhibit anomalous properties, we’ll eventually figure out what is going on to cause superconductivity and then be able to design materials to obtain the properties we want, assuming physics permits them.

The number of arrangements of atoms in a material is effectively infinite and although chemists and material scientists are extraordinarily clever at figuring out how to make structures self-assemble, this represents only an infinitesimal fraction of the possible structures that could be assembled which are chemically and mechanically stable. When we are able to simulate the behaviour of arbitrary structures from ab initio quantum mechanics (which is one of those problems where quantum computing can be put immediately to work for a huge gain in performance) and assemble the structures we design atom-by-atom, as Richard Feynman envisioned in 1960,

But it is interesting that it would be, in principle, possible (I think) for a physicist to synthesize any chemical substance that the chemist writes down. Give the orders and the physicist synthesizes it. How? Put the atoms down where the chemist says, and so you make the substance. The problems of chemistry and biology can be greatly helped if our ability to see what we are doing, and to do things on an atomic level, is ultimately developed – a development which I think cannot be avoided.

This is what molecular nanotechnology is all about and, sooner of later, if we wish to continue to increase the power of our computing devices by scaling them down so they run faster and use less power, that’s the technology we’re eventually going to arrive at. When we get there, it would be surprising if we couldn’t make all kinds of things that natural processes cannot construct.

Here is a talk I gave in 1990 at the Autodesk Technology Forum “What Next? The Coming Revolution in Manufacturing”. As usual, I was (way) early in my predicted dates and over-optimistic in the rate of technological progress (at this epoch, I was just becoming dimly aware of the extent to which academic and national laboratory research in the U.S. was a giant taxpayer-funded trough at which, with rare exceptions, not-very-bright hogs fought for their places for that sweet, sweet government gruel). This became pellucidly evident when the U.S. National Nanotechnology Initiative (NNI) was launched in 2000, only to be immediately hijacked by the swine squad to fund things that had nothing to do with its purported goals, which was achieved by redefining the word “nanotechnology” to mean things nobody had ever used it for previously. Almost a quarter of a century later, NNI still exists, having spent more than US$ 36 billion, essentially none of it on nanotechnology as defined before its creation.

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Too bad it was fake, why dose china make so much stuff up,
I am tired of all this China BS, have they ever invented anything notable? its all a lie.

It was from South Korea. Chinese appear key in explaining it.

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Hmmm! Just off the top of my head … gunpowder, printing, ocean navigation, fine crockery. There is probably a lot more that a historical expert could point to.

Of course, many of those things were later independently re-invented in Europe when the Europeans began to learn what was possible from the likes of Marco Polo. :slightly_smiling_face:

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I’ve seen no evidence that the LK-99 results published by the researchers in South Korea (not China, as noted in comment #39 above) were in any way “fake” (indicative of scientific misconduct, deceptive, or intended to defraud). The synthesis process described was complicated and produces heterogeneous material with a variety of properties. The papers reported that some of the material produced exhibited behaviour indicative of superconductivity: sharp decrease in measured electrical resistance below a critical temperature, zero resistance when measured by the best means available, exclusion of magnetic fields (Meissner effect), and change in specific heat near the critical temperature.

The difficulty in producing material which exhibited these properties from the bulk synthesis process led some of the group to explore fabrication by vapour deposition, which might allow better consistency.

This is the process which other researchers have followed in exploring candidates for high temperature superconductivity ever since the discovery of cuprate superconductors in the 1980s. What appears to have happened here is that some of the team jumped the gun and posted a paper on arXiv which inferred superconductivity from the (genuine) results obtained, setting off a global kerfuffle in attempting to reproduce them.

There has been no assertion of which I am aware that any of the results published were fabricated or in any way “fake”, nor is there any credible motive for the researchers involved to falsify data which they obviously knew others would soon independently attempt to replicate.

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See the Wikipedia article “List of Chinese inventions”. The “Four Great Inventions” are usually considered to be:

  • Papermaking
  • Magnetic compass
  • Gunpowder
  • Printing

Other inventions attributed to China include (in alphabetical order):

  • Banknotes (paper money)
  • Belt drive
  • Blast furnace
  • Cannon
  • Cast iron
  • Civil service examinations (meritocratic administration)
  • Crossbow
  • Gas lighting
  • Horse collar
  • Porcelain
  • Rockets
  • Wheelbarrow
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So, some idiot jumps on a hot news story and puts up a fake video hoping for clicks or notoriety—this is news? This happens all the time and, as has been discussed here at length:

is hardly a new phenomenon, and certainly not confined to China.

The implication of comment #38 was that the results reported by the researchers in the papers posted to arXiv and published in Korea were “fake” and that the perpetrators were in China. Both assertions are false and defame what are likely legitimate scientists who jumped the gun or were too enthusiastic about their results. Unlike others with dubious claims to high temperature superconductivity (see the following posts):

the Korean group published data sufficient to reproduce the synthesis of their material, which others around the world promptly performed, made their independent measurements, and confirmed theorists’ models of the material which did not involve superconductivity. This is how science is supposed to work.

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It’s been a bit over a month since the Great Summer Superconductor Flap of 2023 erupted, and since room temperature superconductors are no longer the Current Thing, they’ve largely disappeared from the news. So now, maybe it’s time to start asking:

Room Temperature Superconductivity — Might There Be Something There After All?

I’ve been expecting this to happen. After the rise and fall of “cold fusion” in 1989, sporadic reports of replications and other experiments indicating something anomalous was going on continued for years, with Infinite Energy magazine, amidst breathy reports of “over-unity” devices and zero-point energy, continued to report on work in "low-energy nuclear reactions”. And even now (quoting from the Wikipedia article):

For example, it was reported in Nature, in May, 2019, that Google had spent approximately $10 million on cold fusion research. A group of scientists at well-known research labs (e.g., MIT, Lawrence Berkeley National Lab, and others) worked for several years to establish experimental protocols and measurement techniques in an effort to re-evaluate cold fusion to a high standard of scientific rigor. Their reported conclusion: no cold fusion.

In 2021, following Nature’s 2019 publication of anomalous findings that might only be explained by some localized fusion, scientists at the Naval Surface Warfare Center, Indian Head Division announced that they had assembled a group of scientists from the Navy, Army and National Institute of Standards and Technology to undertake a new, coordinated study. With few exceptions, researchers have had difficulty publishing in mainstream journals. The remaining researchers often term their field Low Energy Nuclear Reactions (LENR), Chemically Assisted Nuclear Reactions (CANR), Lattice Assisted Nuclear Reactions (LANR), Condensed Matter Nuclear Science (CMNS) or Lattice Enabled Nuclear Reactions; one of the reasons being to avoid the negative connotations associated with “cold fusion”. The new names avoid making bold implications, like implying that fusion is actually occurring.

Ahhhh, yes, the Americans forever changing the names of things to avoid notoriety.

Anyway, here we go with room temperature superconductivity. Here is an opening shot from Tom’s Hardware on 2023-08-24.

But the field of superconductors is a fast-changing one. Newly-published, pre-print theoretical research generally continues to support LK-99 as having the properties required to become a superconductor; and now, internet sleuths have discovered a Korean-language update on the original LK-99 patent. This document presents further details (and also new questions) regarding the synthesis process, even as the original Korean authors reaffirm the significance (and veracity) of their discovery.

Unfortunately, what we’re still left with is an incomplete picture of LK-99 - one that will seemingly require much more effort in understanding than some would lead us to believe. But the paper does have what’s required: a graph plotting LK-99’s resistivity. Crucially, the graph says it does drop to zero.

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But it seems that solid state synthesis wasn’t how Lee’s team discovered the (alleged) emergent superconductivity of LK-99. This was done through a technique known as vapor deposition; through it, the same compounds were reacted, but instead of the objective being to end up with an LK-99 crystal, the technique instead allows for the reaction’s vapors to collect against a glass structure, creating a thin film of the compound. According to Sukbae and his team, this film is forged in the 100 degrees Celsius - 400 degrees Celsius temperature range (with a black film of lead sulfide (PbS) in the lower temp area, a white film of lanarkite (Pb2SO5) in the higher temp area, and a gray film of lead appatite in the intermediate area.

It’s from this gray lead-apatite, micron-thick film that the authors insist room-temperature, ambient-pressure superconductivity emerges. The authors also pre-emptively refer state that impurities of iron (Fe) and other elements also emerge from the synthesis process, and that these impurities are well-known sources of ferromagnetism and diamagnetism - some of the features other studies have already encountered and replicated.

But it may have been premature to consider those results as proof that LK-99 is a dud. According to the authors, these magnetic features make it more difficult to see the actual Meissner Effect in action, with less cautious onlookers assuming that LK-99’s levitation capabilities ended at those types of magnetism.

Which brings us to the latest paper from Vayssilov et al at Sofia University, which also suggests that LK-99 could have the required properties to become a superconductor (do note that once again, there’s no mention of room-temperature or ambient-pressure). The general idea presented in the paper is that there are two ways that could happen: by removing certain oxygen atoms from their places, potential highways for superconductivity appear, with space that was previously occupied by atomic nuclei now being open for electron pairs (the so-called Cooper pairs) to skirt around. Another proposal from the paper is that this same effect can be achieved through the Cu doping we’ve talked about.

Here is the theoretical paper from ChemRxiv, “Alternative Concept of One-Dimensional Superconductivity – Key Role of Defects Revealed by Quantum Chemical Calculations of Lead Apatite” (full text at link). This is the abstract.

Doped lead apatite has been recently reported to feature superconductivity at room temperature and ambient pressure, which may have huge impact on the progress of the humanity in general. The first principle calculations, aiming at understanding the reasons for such behavior, suggest that reduced form of undoped and copper-doped lead apatite contain one dimensional channels, which are free of ions, but with electrostatic potential inside providing conditions for unimpeded electron mobility, potentially leading to superconductivity. Key aspect is that channels are surrounded by lead cations, which generate the necessary electrostatic field but due to their high atomic mass have reduced mobility and do not block the channels even at ambient temperature. Our observations on the modeled structures allowed us to present an alternative concept for features, giving rise of the superconductivity based on chemical understanding of the structure and frontier orbital of the material.

From the start, I found it intriguing that some of the original papers mentioned using vapour deposition as a way to produce uniform material rather than the synthesis process that appears to yield a composite made up of different substances, only some of which exhibit the unusual properties. It will be interesting to see if replications using that (more difficult) technique produce promising results.

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That passage from the article caused me to ignore it when it came out.

The cited document is the KR20230030188 document mentioned in @johnwalker’s original post.

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“Fusion” & “Nuclear” are notorious terms themselves in the context of these technologies which are more like incantations. For all their grounding in theory the engineering of these technologies enjoy, honest names would be “anomalous heat”, “anomalous transmutation” and “anomalous radiation”. Focus on the phenomenology where it belongs when you don’t know what you’re doing and even your measurement instruments are suspect.

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