Two reports have increased my patience factor a lot on this First, a theoretical study found that the phase that’s reported to be superconducting is likely to

Two reports have increased my patience factor a lot on this First, a theoretical study found that the phase that’s reported to be superconducting is likely to be metastable based on some density functional theory calculations. That implies that actually making it may be rather difficult, and raises the bar for reproductions to show exactly what they are finding is superconducting or not. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892 The second study was a comparison of the properties of superconducting Pb thin films with some of the data people have been reporting on LK-99 repro attempts. The authors hypothesize that people are getting micron to several nanometer sized particles of the superconducting phase embedded in an amporphous non-superconducting phase, and that this explains the mixed results. https://arxiv.org/abs/2308.01723 https://arxiv.org/abs/2308.01723 So, more careful analysis is needed and I’m still optimistic. I want to see much better x-ray and microscopic characterization along with the resistance data and so on, especially because the property measurements can be tricky. (My background is materials science but not superconductivity or condensed matter physics if that matters)