On the dynamical stability of copper-doped lead apatite
On the dynamical stability of copper-doped lead apatite
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DOI：
10.1038/s41524-024-01206-9
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发表时间：
2023-09
影响因子：
9.7
通讯作者：
Sun-Woo Kim;Kang Wang;Siyu Chen;L. Conway;G. Pascut;I. Errea;C. Pickard;B. Monserrat
中科院分区：
文献类型：
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作者：
Sun-Woo Kim;Kang Wang;Siyu Chen;L. Conway;G. Pascut;I. Errea;C. Pickard;B. Monserrat
最近，一种名为LK-99的掺铜磷灰石铅化合物的室温超导电性的说法引起了人们的极大兴趣和争议。后来的实验在很大程度上未能重现所声称的超导电性，而理论工作已经确定了多个关键特征，包括强电子关联、结构不稳定性和掺杂性限制。最近几个理论研究的一个令人费解的说法是，母体和掺铜的铅磷灰石结构在谐波水平上都是动态不稳定的，这对数十年来关于母体化合物结构和最近提出的铜掺杂结构的实验报告提出了质疑。在这项工作中，我们证明了母体和掺铜的铅磷灰石结构在室温下都是动态稳定的。非谐声子-声子相互作用对某些掺铜相的稳定起着关键作用，而大多数相即使在谐和水平上也是基本稳定的。我们还发现动力学稳定性依赖于体积和关联强度，这为探索掺铜铅磷灰石结构相图提供了可控的途径。我们的结果完全符合理论描述的母体和掺铜铅磷灰石的结构与实验。
The recent claim of room temperature superconductivity in a copper-doped lead apatite compound, called LK-99, has sparked remarkable interest and controversy. Subsequent experiments have largely failed to reproduce the claimed superconductivity, while theoretical works have identified multiple key features including strong electronic correlation, structural instabilities, and dopability constraints. A puzzling claim of several recent theoretical studies is that both parent and copper-doped lead apatite structures are dynamically unstable at the harmonic level, questioning decades of experimental reports of the parent compound structures and the recently proposed copper-doped structures. In this work, we demonstrate that both parent and copper-doped lead apatite structures are dynamically stable at room temperature. Anharmonic phonon–phonon interactions play a key role in stabilizing some copper-doped phases, while most phases are largely stable even at the harmonic level. We also show that dynamical stability depends on both volume and correlation strength, suggesting controllable ways of exploring the copper-doped lead apatite structural phase diagram. Our results fully reconcile the theoretical description of the structures of both parent and copper-doped lead apatite with the experiment.