The noncentrosymmetricity of a prototypical correlated electron system Ca 3 Ru 2 O 7 renders extensive interest in the possible polar metallic state, along with multiple other closely competing interactions. However, the structural domain formation in this material often complicates the study of intrinsic material properties. It is crucial to fully characterize the structural domains for unrevealing underlying physics. Here, we report the domain imaging on Ca 3 Ru 2 O 7 crystal using the reflection of polarized light at normal incidence. The reflection anisotropy measurement utilizes the relative orientation between electric field component of the incident polarized light and the principal axis of the crystal, and gives rise to a peculiar contrast. The domain walls are found to be the interfaces between 90° rotated twin crystals by complementary magnetization measurements. A distinct contrast in reflectance is also found in...

中文翻译：

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偏光反射法在非中心对称Ca 3 Ru 2 O 7中的结构域成像和晶体取向的直接确定

原型相关电子系统Ca 3 Ru 2 O 7的非中心对称性引起了人们对可能的极性金属态以及其他紧密竞争的相互作用的广泛关注。但是，这种材料中结构域的形成通常会使内在材料性能的研究复杂化。至关重要的是，充分表征结构域，以揭示基础物理学。在这里，我们报告了使用垂直入射的偏振光反射对Ca 3 Ru 2 O 7晶体进行的畴成像。反射各向异性测量利用入射的偏振光的电场分量与晶体的主轴之间的相对取向，并产生独特的对比度。通过互补磁化测量发现，畴壁是90°旋转的双晶之间的界面。反射率也有明显的反差。