Recently, kagome lattice materials have emerged as a new model material platform for discovering and engineering novel quantum phases of matter. In this work, we elucidate the driving mechanism of the \(\sqrt{{{3}}}\)×\(\sqrt{{{3}}}\) charge order in a newly discovered kagome metal ScV₆Sn₆. Through multimodal investigations combining angle-resolved photoemission spectroscopy, phonon dispersion calculations, and phase diagram study, we identify the central role of unstable planar Sn and Sc phonon modes, while the electronic instability and van Hove singularities originating from the V kagome lattice have a marginal influence. Our results highlight that the \(\sqrt{{{3}}}\)×\(\sqrt{{{3}}}\) charge order in ScV₆Sn₆ is fundamentally distinguished from the electronically driven 2 × 2 charge order in the canonical kagome system AV₃Sb₅, uncovering a new mechanism to induce symmetry-breaking phase transition in kagome lattice materials.

最近，kagome 晶格材料已成为发现和工程新型物质量子相的新模型材料平台。在这项工作中，我们阐明了新发现的 kagome 金属 ScV ₆ Sn _6中\(\sqrt{{{3}}}\) × \(\sqrt{{{3}}}\)电荷顺序的驱动机制。通过结合角分辨光电子能谱、声子色散计算和相图研究的多模态研究，我们确定了不稳定平面 Sn 和 Sc 声子模式的核心作用，而源自 V kagome 晶格的电子不稳定性和 van Hove 奇点则具有边缘作用。影响。我们的结果强调，ScV ₆ Sn _6中的\(\sqrt{{{3}}}\) × \(\sqrt{{{3}}}\)电荷顺序与电子驱动的 2 × 2 电荷有根本区别经典 Kagome 系统 AV ₃ Sb ₅中的顺序，揭示了一种在 Kagome 晶格材料中诱导对称破缺相变的新机制。