Discovery of low-dimensional materials has been of great interest in physics and material science. Optical permittivity is an optical fingerprint of material electronic structures, and thus it is an important parameter in the study of the properties of materials. Spectroscopic ellipsometry provides a fast, robust, and noninvasive method for obtaining the optical permittivity spectra of newly discovered materials. Atomically thin low-dimensional materials have an extremely short vertical optical path length inside them, making the spectroscopic ellipsometry of low-dimensional materials unique, compared to traditional ellipsometry. Here, we introduce the fundamentals of spectroscopic ellipsometry for two-dimensional (2D) materials and review recent progress. We also discuss technical challenges and future directions in spectroscopic ellipsometry for low-dimensional materials.

中文翻译：

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用于低维材料和异质结构的光谱椭偏仪

低维材料的发现一直引起物理学和材料科学的极大兴趣。介电常数是材料电子结构的光学指纹，是研究材料性能的重要参数。光谱椭偏仪为获得新发现材料的光学介电常数光谱提供了一种快速、稳健且无创的方法。原子级薄的低维材料内部具有极短的垂直光路长度，与传统的椭偏仪相比，低维材料的光谱椭偏仪具有独特性。在这里，我们介绍了二维 (2D) 材料的光谱椭偏仪的基本原理，并回顾了最近的进展。