论文标题
几层铬三碘化物中的非肾脏第二次谐波产生
Nonreciprocal Second-Harmonic Generation in Few-Layer Chromium Triiodide
论文作者
论文摘要
同时识别二维范德华材料的原子和磁性构型是至关重要的，但具有挑战性。在这项工作中，我们表明非重生第二次谐波一代（SHG）可能是应对这一挑战的强大工具。尽管保留了晶格反演对称性，但层间抗铁磁序和自旋轨道耦合在PT对称双层三碘化物（CRI3）中会产生增强的SHG（CRI3）。重要的是，平面偏振分辨的SHG对线性光谱无法说明的微妙的层间结构敏感。除了双层外，我们还进一步预测，可以使用强度和角度分辨的SHG来识别层间原子和磁性构型。我们的第一原理结果与可用的测量结果一致，并显示了SHG作为探索层间结构与新兴超薄磁性材料之间相关性的一种非接触式方法的潜力。
It is of fundamental importance but challenging to simultaneously identify atomic and magnetic configurations of two-dimensional van der Waals materials. In this work, we show that the nonreciprocal second-harmonic generation (SHG) can be a powerful tool to answer this challenge. Despite the preserved lattice inversion symmetry, the interlayer antiferromagnetic order and spin-orbit coupling generate enhanced SHG in PT-symmetric bilayer chromium triiodide (CrI3). Importantly, the in-plane polarization-resolved SHG is sensitive to subtly different interlayer structures that cannot be told by linear optical spectra. Beyond bilayer, we further predict that the intensity and angle-resolved SHG can be employed to identify both interlayer atomic and magnetic configurations of trilayer CrI3. Our first-principles results agree with available measurements and show the potential of SHG as a non-contacting approach to explore correlations between interlayer structures and magnetic orders of emerging ultra-thin magnetic materials.
