近年来,光学二次谐波(SHG)现象作为一种关键的非线性光学效应引起了人们的广泛关注。值得注意的是,在低维材料(LDM)中,由于SHG具有明显的二阶磁化率和独特的电子结构,因此SHG检测已成为阐明非线性光学特性的仪器工具。这篇综述提供了此类材料中SHG的生成过程和实验配置的详尽概述。它强调了利用SHG作为研究这些材料的非线性光学属性的灵敏探针的最新进展,特别关注其在揭示电子结构方面的关键作用,带隙特性,和晶体对称。通过分析SHG信号,研究人员可以对这些材料的微观特性收集宝贵的见解。此外,本文深入研究了光学SHG在成像和时间分辨实验中的应用。最后,讨论了LDM中NLO改进的未来方向和挑战,为这一快速发展的领域提供了展望,为相关设备的设计和优化提供了关键的观点。
In recent years, the phenomenon of optical second harmonic generation (
SHG) has attracted significant attention as a pivotal nonlinear optical effect in research. Notably, in low-dimensional materials (LDMs),
SHG detection has become an instrumental tool for elucidating nonlinear optical properties due to their pronounced second-order susceptibility and distinct electronic structure. This review offers an exhaustive overview of the generation process and experimental configurations for
SHG in such materials. It underscores the latest advancements in harnessing
SHG as a sensitive probe for investigating the nonlinear optical attributes of these materials, with a particular focus on its pivotal role in unveiling electronic structures, bandgap characteristics, and crystal symmetry. By analyzing
SHG signals, researchers can glean invaluable insights into the microscopic properties of these materials. Furthermore, this paper delves into the applications of optical SHG in imaging and time-resolved experiments. Finally, future directions and challenges toward the improvement in the NLO in LDMs are discussed to provide an outlook in this rapidly developing field, offering crucial perspectives for the design and optimization of pertinent devices.