标题： 双偏振SHG干涉术用于成像二维异质晶体的反平行畴和堆叠角度 显示英文标题

标题： Dual-Polarization SHG Interferometry for Imaging Antiparallel Domains and Stacking Angles of 2D Heterocrystals

摘要： 光学二次谐波产生（SHG）能够用于晶体学分析和多种材料的畴成像的取向偏振测量。然而，传统的强度偏振测量方法忽略了相位信息，无法区分反平行畴，并且不能描述代表一类新的范德华力结合复合晶体的二维异质结构。在这项工作中，我们报告了双偏振光谱相位干涉仪（DP-SPI），并建立了一个包含DP-SPI可观测量的广义SHG叠加模型。单层过渡金属二硫属化物（TMD）的反平行畴成功地以区分的方式成像，验证了干涉偏振测量。从TMD异质双分子层的DP干涉图中，可以确定每层的取向，从而实现分层分辨探测。通过使用叠加模型，我们还展示了具有圆偏振SHG的三元TMD异质结构的光子设计和制造。这些方法提供了全面的SHG测量和理论描述，可以扩展到由多于两层成分构成的异质结构，并不仅限于TMDs或二维材料。 显示英文摘要

摘要： Optical second-harmonic generation (SHG) enables orientational polarimetry for crystallographic analysis and domain imaging of various materials. However, conventional intensity polarimetry, which neglects phase information, fails to resolve antiparallel domains and to describe two-dimensional heterostructures, which represent a new class of van der Waals-bound composite crystals. In this work, we report dual-polarization spectral phase interferometry (DP-SPI) and establish a generalized SHG superposition model that incorporates the observables of DP-SPI. Antiparallel domains of monolayer transition metal dichalcogenides (TMDs) were successfully imaged with distinction, validating the interferometric polarimetry. From DP interferograms of TMD heterobilayers, the orientation of each layer could be determined, enabling layer-resolved probing. By employing the superposition model, we also demonstrate the photonic design and fabrication of ternary TMD heterostructures for circularly polarized SHG. These methods, providing comprehensive SHG measurements and theoretical description, can be extended to heterostructures consisting of more than two constituent layers and are not limited to TMDs or 2D materials.