声学波函数成像研究Kagome晶格中的子格物理
Acoustic Wave-Function Imaging of Sublattice Physics in a Kagome Lattice
- Julius-Maximilians-Universität Würzburg（维尔茨堡大学）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本研究通过厘米尺度声学Kagome晶格测量完整激发谱并成像波函数，首次直接观测到子格分辨的能带结构，验证了平带与范霍夫奇点的子格纹理。
中文摘要 AI 辅助
典型的Kagome能带结构包含狄拉克锥、鞍点范霍夫奇点（vHS）和一条平带。这些特征在Kagome晶格的三位基内表现出不同的子格局域化。然而，这种子格特性的实验证明具有挑战性，需要直接获取实空间波函数及其相关的动量空间纹理。在此，我们在厘米尺度上构建了一个声学Kagome晶格，并测量了完整的激发谱，从而对每个晶格位点的波函数（包括振幅和相位）进行成像。这使得我们能够研究整个能带结构中动量依赖的子格纹理，特别是在平带以及混合和纯子格范霍夫奇点处。我们的结果与最小紧束缚模型计算高度吻合，构成了对Kagome晶格中子格分辨能带结构的首次直接实验观测。
英文摘要
The canonical kagome band structure hosts a Dirac cone, saddle-point van Hove singularities (vHS), and a flat band. Characteristically, these features exhibit distinct sublattice localization within the three-site basis of the kagome lattice. However, experimental proof of this sublattice character is challenging and requires direct access to both the real-space wave function and its associated momentum-space texture. Here, we implement an acoustic kagome lattice on the cm scale and measure the full excitation spectrum, thereby imaging the wave function at each lattice site, including both amplitude and phase. This enables investigation of the momentum-dependent sublattice texture across the complete band structure, particularly at the flat band and at the mixed- and pure-sublattice van Hove singularities. Our results are in excellent agreement with minimal tight-binding model calculations and constitutes the first direct experimental observation of the sublattice-resolved band structure in a kagome lattice.
