Zero Resistance Measured in a New LK-99 Replication at Southeast University in Nanjing China

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A team of scientists from the Physics Department of Southeast University, a top university in Nanjing, China, have reported measuring 0 resistance in a sample of LK-99 they synthesized from scratch. Claimed to have synthesized LK-99 and to have measured superconductivity up to a temperature of 110 kelvin. Claimed to have observed an abrupt drop in resistance between ~300K and 220K, aligning with the Korean LKK team’s results. Claimed to have confirmed structural consistency with x-ray diffraction.

UPDATE: Physics Department of Southeast University has published a preprint paper on Arxiv for the work covered in this video.

From the video:
– They measure 0 resistance at 110K (-163C) using the four-point probe method. 0 resistance at this high of a temperature at ambient pressure is a new discovery in materials science
– They also claim a transition in and out of zero resistance state depending on a strongly applied magnetic field – a classic characteristic of superconductivity.
– The sample they synthesized is reported to have much higher purity than the original Korean team of LKK
– They note an interesting and abrupt drop in resistance, by several orders of magnitude, between ~300 and 220K (approx values from the graph). This is currently unexplained, but is in rough agreement with LKK – i.e., LKK may have been measuring this higher-temperature ‘drop’ which was two orders of magnitude.
– They retain the claim that this is not absolute conclusive proof of superconductivity, but it is suggestive of very interesting electronic properties in this material.

These results compare nicely with recent simulations out of Lawrence Berkeley National Lab, University of Boulder Colorado, Shenyang National Laboratory, and TU Wien, all performed by high profile and established materials scientists.

Those simulations have converged on LK-99 having the potential for superconductivity at high temperatures and ambient pressures due to the formation of flat energy bands when lead-apatite crystal is doped with copper. Notably, other doping metals may also achieve similar or better performance.

Here is the link to the Targum translation of the video

I am Sun Yuyue from the School of Physics at Southeast University. Today, I would like to report to you the latest research findings of our group on LK99. Recently, the topic of extraterrestrial super islands has been very hot. We have seen many reports on this. As researchers in the field of super islands, we are very happy. We have received a lot of interest in our work. However, we have also noticed that some media or self-media outlets have been over-reporting or distorting our experimental results. Therefore, I would like to take this opportunity to introduce our findings to you through this video. Our work has already been published in the journal Account, so you will soon be able to read the full article.

First of all, let me clarify the most important point. We have neither confirmed nor discovered extraterrestrial super islands. However, we have successfully observed zero resistance below 110K. This could be an important piece of evidence for the existence of superconductivity in this material. Now, let’s take a look at the paper and provide you with a detailed explanation.

Let me first introduce our research team at the School of Physics, Southeast University. This work was mainly carried out by three students: Hou Qiang, Wei Wei, and Zhou Xing. Professor Shi Yang and I also contributed to this work. Now, let’s directly examine the figures in our paper and explain them to you.

The first figure shows our X-ray diffraction results. On the left are the XRD results of two precursor materials. On the right are the XRD results of the materials we synthesized. We conducted X-ray diffraction on four batches of samples. We compared our X-ray results with those reported by a team from South Korea. The X-ray patterns of our samples match very well with the reported ones. In fact, our samples are even purer than theirs. The peak corresponding to impurities in their samples is much smaller in ours. Therefore, we can say that our samples have a higher level of purity.

Now, let’s move on to the most important part – the zero resistance results. Let’s take a closer look at our measurements. We started measuring from 300K and gradually decreased the temperature. The current passing through the sample was one milliampere. Due to the fragility of the sample, it was difficult to shape it into a regular form. Therefore, we used an irregularly shaped sample to save time. We measured the resistivity using the four-probe method. Under a current of one milliampere, we observed that the resistivity exhibited slight semiconductor behavior at high temperatures. As the temperature decreased, the resistivity decreased as well. The most crucial observation was made at 110K. At this temperature, we observed that the resistance approached zero. Why do we say it approached zero? If you look at the scale of the resistance on this side, it is around 10^-5 to 10^-6 ohms. Considering the current of one milliampere, the corresponding voltage is around 10^-8 or 10^-9 volts. This is within the measurement range of our instrument, PBMS. Therefore, we believe that we have observed zero resistance.
This is our sample. In our previous experiments, we observed a strange drop in resistance at around 250K. The cause of this drop is still unknown. It may be due to some impurities or other factors in the measurement setup. We are still investigating this phenomenon. We also conducted measurements of the superconducting transition under a magnetic field. We observed that the superconducting transition remained relatively stable under the applied magnetic field. The critical temperature, TC0, showed only a slight variation. However, there were some peculiarities in the superconducting transition under different magnetic fields. For example, at low fields such as 0 Tesla and 135 Tesla, the superconducting transition shifted to lower temperatures as the magnetic field increased. However, at 9 Tesla and 7 Tesla, the superconducting transition seemed to revert back. The reason for this behavior is still unknown.
Finally, I would like to mention that we first observed a sharp drop in resistivity similar to a superconducting transition on the afternoon of August 1st. However, at that time, the resistivity did not reach zero and had a small value. Therefore, we intensified our sample selection process. We tested a total of six samples, but we only observed zero resistance in one of them. In most of the other samples, we observed behavior characteristic of semiconductors. In addition, we performed measurements of the Meissner effect on the sample with zero resistance. However, we did not observe complete diamagnetism in the magnetic measurements. Therefore, we speculate that if the zero resistance in our sample is caused by superconductivity, its superconducting component is relatively low.
This concludes the main findings of our work. I would like to express my sincere gratitude to the three students who worked diligently on this project. I would also like to reiterate the most important points. We have successfully observed zero resistance below 110K in the LK99 material. However, this does not constitute evidence of room temperature superconductivity. Further exploration and measurements are needed to determine if room temperature superconductivity exists. Our team will continue to make efforts in this direction. We hope to bring you better results in the future. Thank you, everyone.

11 thoughts on “Zero Resistance Measured in a New LK-99 Replication at Southeast University in Nanjing China”

  1. This looks very much like an insulator behavior. The decrease of resistance is caused by the shift of current paths or compliance of the source. The dislocation to higher temperatures in the presence of magnetic field is caused by this point being achieved earlier due to magnetoresistance.

    There is nothing great about this work.

    Looks like people forgot how to measure superconductivity. Like, measure RxT at different currents and show 2 and 4 probe measurements. Also, IxVs near Tc go a long way. This is so sad to see. And blogs like this just make things worse

  2. (yes, with the Parody knob turned to ’10’) … So this is great! Let’s make plans to colonize Luyten b or Cancri e (nearby Earth-like exoplanets, in the Goldilocks zone of their star) by superconducting warp drive!!! What the F are we waiting for!

    Turning it off … I’m left with the observation that something unusual has been observed, and something which at present is pretty anisotropic (different effect depending on orientation). This doesn’t spell doom to the nascent discovery: let us remember that the very early days of the so-called High-Tc cuprate superconductors was similarly plagued with all sorts of anisotropies and exceptional phenomena. JUST as we now can cite that the same cuprate High-Tc superconductors are critically important enabling tech for the worldwide roll-out of magnetic resonance imaging (MRI) non-invasive medical diagnosis machines. No Hi-Tc, and they’d still be so outrageously priced that only a handful of universities and major well funded metropolitan hospitals could have ’em.

    Now they’re virtually everywhere.

    So, the take-away is, sure this doesn’t enable Warp Drives (and likely won’t, ever), but it certainly could be researched-and-evolved into making powerful magnetic field machines that work at ambient temperatures, requiring no more than a cage full of good fans to keep it ‘cool enough’. MRI in your dentist’s office? Maybe!

    ⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
    ⋅-=≡ GoatGuy ✓ ≡=-⋅

    • I think this is more spot on. I remember the early days of YBCO which I used as an analogy in a comment on another article.

  4. 110K may be nice for superconductors but it is a tad chilly for me as a standard of “room temperature” is the drop in resistance but not zero resistance at higher temperatures still useful or is this just a new cold “high temperature” superconductor?

    • Even if it’s only a superconductor below 110K, the material is still useful to help us understand how to engineer higher temperature superconductors. On its own LK99 anyways isn’t that practical, as even the alleged superconductivity is lost at a low current threshold.

  5. I’m getting strong Pons and Fleischmann cold fusion vibes from this one. Lots of hasty replications showing contradictory results.

    The big difference being that the material, despite the obtained amounts, if it works it would be superconductor and statically stable at room temperature, ergo can be stored and sent for anyone to take a look later.

    A speck of rock that shows Meissner effect without any refrigeration is kind of an “Eppur si Muove” argument for superconductivity.

    • This is all consistent with the theoretical predictions, actually:
      – There are two possible crystallographic sites where the copper can go.
      – If it goes in the wrong one, you get a semiconductor. If it goes in the right one, you *may* get a superconductor.
      – Unfortunately, the wrong site is energetically favored, so most samples would have the copper in the wrong place, and won’t be superconducting.
      – Even in the “good” samples, you may have a mix of some of the copper in the right place, and some in the wrong place.
      – Then there’s impurities and grain boundaries complicating things, and the prediction that even when it’s superconducting, it’s only superconducting in one direction.
      – Finally, there seems to some need for oxygen doping as well.

      It’s all pretty finicky, but does look like something is there.

      • I imagine there will be a lot of effort put into constraining the doping into site 2. Very early days!

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