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arXiv:2307.16892cond-mat.supr-con

Origin of correlated isolated flat bands in copper-substituted lead phosphate apatite

Sinéad M. Griffin

Abstract

A recent report of room temperature superconductivity at ambient pressure in Cu-substituted apatite (`LK99') has invigorated interest in the understanding of what materials and mechanisms can allow for high-temperature superconductivity. Here I perform density functional theory calculations on Cu-substituted lead phosphate apatite, identifying correlated isolated flat bands at the Fermi level, a common signature of high transition temperatures in already established families of superconductors. I elucidate the origins of these isolated bands as arising from a structural distortion induced by the Cu ions and a chiral charge density wave from the Pb lone pairs. These results suggest that a minimal two-band model can encompass much of the low-energy physics in this system. Finally, I discuss the implications of my results on possible superconductivity in Cu-doped apatite.

arXiv comments
Journal reference
DOI
Subjects
cond-mat.supr-conSuperconductivity cond-mat.mtrl-sciMaterials Science cond-mat.str-elStrongly Correlated Electrons

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Linked by 11 identifiable commenters in 13 comments across 7 threads, from Aug 2023 to Aug 2023. Found in 2 HN submissions from Aug 2023 to Aug 2023. Open submission discussions.

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Discussed in comments7 threads

  1. Compilation of claims/reports of LK-99 replication efforts 1 comment

    • 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…

      rsfernView on HNParent context

  2. Successful room temperature ambient-pressure magnetic levitation of LK-99 1 comment

    • >Most likely, the material LK99 as reported in [1-3] is a heterophase structure, with co-existent non-superconducting constituents. This may yield superconducting droplets surrounded by nonsuperconducting material... https://arxiv.org/abs/2308.01723 >In fact, I find that Cu on…

      httpzView on HNParent context

  3. LK-99: Team of Southeast University observed zero resistance below 110 K 2 comments

    • Seems like it may depend on getting specific binding sites. > Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key characteristics for high-TC superconductivity, namely a particularly flat isolated d-manifold…

      trafficanteView on HNParent context

    • > purity as in the sample is uniformly constructed of the right atoms but they are not in the right configuration The conclusions in the linked pdf suggest this may be the issue with LK99. 1. https://arxiv.org/abs/2307.16892

      trafficanteView on HNParent context

  4. Electronic Structure of LK-99 2 comments

    • More specifically they agree with another similar paper from Stanford's Sinead Griffin https://arxiv.org/abs/2307.16892

      zeronullemptyView on HNParent context

    • "Origin of correlated isolated flat bands in copper-substituted lead phosphate apatite" (2023) https://arxiv.org/abs/2307.16892 : > Abstract: A recent report of room temperature superconductivity at ambient pressure in Cu-substituted apatite (`LK99') has invigorated interest in…

      westurnerView on HNParent context

  5. A room-temperature superconductor? New developments 1 comment

    • While you're correct about the scarce and sketchy evidence currently it is in the process of narrowing down. Or to put it better the evidence is mounting that it might be a breakthrough. It likely hard to manufacture correctly, but simulations done at Berkeley Labs seem to…

      throwaway23354View on HNParent context

  6. Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2 2 comments

    • I just wrote a comment in another thread that's relevant here too. It looks like the first superconductor paper was released by a rouge researcher, without the agreement of the other two authors or the rest of the LK-99 group. This forced the LK-99 group to rush to publish the…

      joefiguraView on HNParent context

    • Preprint by Griffin from Livermore Labs gives a theoretical explanation of LK-99's superconductivity and also explains why labs are having a hard time synthesizing it. There are two Pb sites in the crystal structure that Cu can substitute at, the lower energy one does nothing…

      jbogganView on HNParent context

  7. Semiconducting Transport in LK99 reproduction attempt 4 comments

    • Research out of Berkeley, 1 Aug 2023: theoretical analysis suggests high-Tc superconductors from apatite possible, points to synthesis challenges. > Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key…

      carabinerView on HNParent context

    • They're talking about a newer paper that provides some reason for optimism. https://arxiv.org/abs/2307.16892

      tatrajimView on HNParent context

    • I think this theoretical result by Griffin at the Livermore Lab explains why labs are having difficulty replicating the LK-99 sample: https://arxiv.org/pdf/2307.16892.pdf There are basically two repeating crystal cells. Her theoretical calculation shows superconducting…

      jbogganView on HNParent context

    • Seems there is new support that its legit! https://twitter.com/Andercot/status/1686215574177841152 National Lab (LBNL) results support LK-99 as a room-temperature ambient-pressure superconductor. Simulations published 1 hour ago on arxiv support LK-99 as the holy grail of modern…

      redmView on HNParent context

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