Dasgupta Arindam, Yang Xiaodong, Gao Jie
Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, MO, 65409, USA.
Department of Mechanical Engineering, Stony Brook University, Stony Brook, NY, 11794, USA.
Sci Rep. 2022 Jun 15;12(1):10006. doi: 10.1038/s41598-022-14046-8.
Cannizzarite is a naturally occurring mineral formed by van der Waals (vdW) stacking of alternating layers of PbS-like and BiS-like two-dimensional (2D) materials. Although the PbS-type and BiS-type 2D material layers are structurally isotropic individually, the forced commensuration between these two types of layers while forming the heterostructure of cannizzarite induces strong structural anisotropy. Here we demonstrate the mechanical exfoliation of natural cannizzarite mineral to obtain thin vdW heterostructures of PbS-type and BiS-type atomic layers. The structural anisotropy induced anisotropic optical properties of thin cannizzarite flakes are explored through angle-resolved polarized Raman scattering, linear dichroism, and polarization-dependent anisotropic third-harmonic generation. Our study establishes cannizzarite as a new natural vdW heterostructure-based 2D material with highly anisotropic optical properties for realizing polarization-sensitive linear and nonlinear photonic devices for future on-chip optical computing and optical information processing.
钙钛矿是一种天然存在的矿物，由类硫化铅（PbS）和类硫化铋（BiS）二维（2D）材料的交替层通过范德华（vdW）堆叠形成。尽管PbS型和BiS型二维材料层各自在结构上是各向同性的，但在形成钙钛矿异质结构时，这两种类型的层之间的强制共格会诱导出强烈的结构各向异性。在此，我们展示了对天然钙钛矿矿物进行机械剥离，以获得PbS型和BiS型原子层的薄vdW异质结构。通过角分辨偏振拉曼散射、线性二向色性和偏振相关的各向异性三次谐波产生，探索了薄钙钛矿薄片中由结构各向异性诱导的各向异性光学性质。我们的研究将钙钛矿确立为一种基于新型天然vdW异质结构的二维材料，具有高度各向异性的光学性质，可用于实现未来片上光学计算和光学信息处理的偏振敏感线性和非线性光子器件。
