Is LK-99 a Superconductor After All? New Research and Updated Patent Say So

Levitating Substance (not LK-99)
(Image credit: Shutterstock (2347353021))

Earlier this month, the science community was abuzz with news of a possible breakthrough: a substance called LK-99 that's alleged to be a room-temperature superconductor. Discovered by Lee Sukbae and Kim Ji-Hoon from Korea university, the material would be a game changer for everything from power delivery to super computers, if it works as advertised. However, after a number of scientists tried and failed to reproduce Lee and Kim's' findings, the world seems to have moved on. 

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.

Diagram from the patent update

The graph above showcases what's generally to be expected of a superconductor: a falling resistivity cliff around a phase-transition critical temperature (Tc). Of course, graphs are easy to plot; it's more difficult to replicate the results that should lead to them. (Image credit: Lee Sukbae et al)

Let's start with the updated patent itself, which describes two techniques to synthesize the relevant, superconducting bits in LK-99. One of those techniques is one we know already: solid state synthesis is the process we followed across the internet, and the one being used by most scientists attempting to replicate the original paper's really bad recipe. It involves reacting the different compounds within LK-99 in order to obtain a crystal-like final compound of copper-doped lead apatite (mixing lanarkite and copper phosphide, themselves compounds made from reacting lead oxide with lead sulfide and reacting copper with phosphorous, respectively).

There were already a number of problems with the actual recipe, but the updated patent throws yet another wrench in the equation by suddenly including Si (the silicon we know and love) within the mixture. It's also unclear how silicon got there and how relevant it is for the superconduction itself (if it's relevant for that at all, which currently doesn't seem like it is). There does seem to be a pattern in which the original Korean team led by Lee Sukbae isn't able to provide good documentation. In fairness, it's also possible that crucial details are simply lost within the bowels of machine translation, or to the speed at which they've seemingly put everything together.

At the same time, the authors admit that yes, the resulting lead-apatite compound is typically an insulator (which prevents electrical current from coursing through it, the exact opposite of what we're trying to achieve here). But they also reiterate that copper doping - which leads to lead atoms being replaced with copper atoms within LK-99 - is key to unlock the claimed superconductivity capability (oxygen atoms are also important, it seems). We already covered this possibility in more detail here, as well as the issue with yield (the proportion of  superconducting material produced through the synthesis process). According to the updated patent, Lee's team saw samples with a ratio of 48.9% superconductive lead apatite; 40% of non-superconductive lead compounds; and copper compounds (11.1%).

This coexistence between superconductive and non-superconductive compounds may be the reason why certain LK-99 internet videos (if legitimate LK-99) showcased a phenomenon dubbed flux pinning, where external magnetic fields are able to penetrate the superconductor compound through the parts of it that aren't superconductive (everything that isn't lead-apatite), pinning it in place.

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.

Diagram from the updated Korean patent.

According to the authors, there are three critical temperature (Tc) junctions where LK-99 shifts phase: at ~125; ~80; and ~50 degrees Celsius (Tc I corresponding to the second yellow arrow, and Tc II to the first yellow arrow). (Image credit: Lee Sukbae et all)

The precise method to identify and measure the Meissner Effect's telltale repulsion of external magnetic fields lies in applying a very low magnetic field with what's called a Superconducting Quantum Interference Device (SQUID). If done while heating and cooling LK-99, the SQUID will then be able to detect the Meissner Effect as it emerges within LK-99's superconducting state: within two of its three critical temperature phase transitions. These phase transitions themselves correspond to changes in the material's structure that then allow superconductivity (the ordered and resistivity-less movement of electrons) to occur.

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.

From the paper

With the additional space between subatomic particles (quanta) resulting from the reduction of oxygen or copper atoms, electron pairs also known as Copper pairs are able to team-up and zip through the material without any energy losses. (Image credit: Georgi N. Vayssilov et all)

Following this LK-99 saga, there's also been a few articles posted to Arxiv that don't necessarily deal with LK-99 itself, but with certain systematic errors and incomplete knowledge on magnetism surrounding superconductor research and the theory applied to reach (supposedly correct) results. 

The authors say that they have run LK-99 through a scanning electron microscope in all of its phases as they occur in both production outputs (the film from vapor deposition and the compound from solid state synthesis). According to them, it's easier to measure and replicate LK-99's superconductivity results in the film-like material. 

With the authors' description of how to detect the Meissner effect now published, additional researchers may apply this new knowledge to their replication attempts. Whether or not that will result in any positive replications - and whether that will come sooner rather than later - remains to be seen.

Francisco Pires
Freelance News Writer

Francisco Pires is a freelance news writer for Tom's Hardware with a soft side for quantum computing.

  • A Stoner
    The speed at which this story moved originally was way too fast, and the period of time between start to declaring failure was far too short.

    There is quite a bit of competition out there for research dollars and researcher hours each of which is limited in supply while being nearly infinitely in demand.

    So there are reasons to give up on dead end research and move on to the next idea quickly. Of course, if you write something off as a dead end before it is proven to be a dead end, that likely cuts that research out of any opportunity to be discovered ever.

    Hopefully this fleshes out and we do end up with a superconductor in the normal temperature and pressure ranges of human existence and our lives can be greatly improved.
    Reply
  • InvalidError
    A Stoner said:
    Hopefully this fleshes out and we do end up with a superconductor in the normal temperature and pressure ranges of human existence and our lives can be greatly improved.
    Discovering a new material is a whole other ball game from turning it into a useful, economically viable material. Tons of promising research gets crapped because the discoveries cannot be applied in a practical or cost-effective manner. At least not until something gets discovered later that solves some of the problems and prompts researchers to check whether it is enough to attempt reviving dropped projects with.
    Reply
  • Giroro
    I declare shenanigans, and hereby invoke my established right of "pics or it didn't happen".
    Reply
  • Ryan F. Mercer
    A Stoner said:
    The speed at which this story moved originally was way too fast, and the period of time between start to declaring failure was far too short.

    Damn...! Stoner be on point.
    Reply
  • jkflipflop98
    Well I know beyond a shadow of a doubt this is real. And it's not new.
    Reply
  • CFT
    When you declare you have found a functioning superconductor to the scientific community and the press, you should already have your ducks in a row and be ready to publish, it's called 'd o c u m e n t a t i o n'. LK 99's handling has been one long murky ball of attention gathering nothing, much like Pons-fleischmann. The scientists should have themselves reproduced their work before proceeding with their finding.
    You don't get to change your story, or your secret formula over and over again and claim discovery.Here's the kicker, if someone else looks at your method, and tried something else that actually works, and then they properly document their method correctly and then publish, and the work can actually be reproduced, then they should be the ones to get credit.
    Reply
  • tennis2
    CFT said:
    When you declare you have found a functioning superconductor to the scientific community and the press, you should already have your ducks in a row and be ready to publish, it's called 'd o c u m e n t a t i o n'. LK 99's handling has been one long murky ball of attention gathering nothing, much like Pons-fleischmann. The scientists should have themselves reproduced their work before proceeding with their finding.
    You don't get to change your story, or your secret formula over and over again and claim discovery.Here's the kicker, if someone else looks at your method, and tried something else that actually works, and then they properly document their method correctly and then publish, and the work can actually be reproduced, then they should be the ones to get credit.
    Absolutely. Once you tell the world, you're racing against everyone else, and a material discovery like this isn't going to be ignored. If/when someone else properly figures it out, it doesn't have to be much different for them to get credit. Your product and procedure either works or it doesn't, otherwise it's just a "suggestion".

    Claiming that "the magic is in there somewhere, our process/sample is just too dirty" isn't Nobel prize worthy IMO
    Reply
  • InvalidError
    tennis2 said:
    Claiming that "the magic is in there somewhere, our process/sample is just too dirty" isn't Nobel prize worthy IMO
    If they want to prove their material's properties without giving their full process away, they can always send some of their own samples out for others to independently pick apart and test. They said they would send some samples out, don't remember reading about anyone receiving those yet.

    No matter what the exact recipe and process are, independently verified results on the mystery golden samples would be a bombshell that would blow the floodgates on money to find out if it can be turned into economically or at least strategically viable products.
    Reply
  • TheSector
    Admin said:
    This alleged scientific breakthrough has some new evidence to support its discoverers claims.

    Is LK-99 a Superconductor After All? New Research and Updated Patent Say So : Read more
    Fly the Korean cooks to Argonne. Share a lab and make it happen.
    Reply
  • Francis412
    This looks more and more like Cold Fusion.
    Reply