摘要
作为一种非线性光学效应,二次谐波产生(second harmonic generation,SHG)因其良好的偏振敏感性在获得物质成分、结构、特性等信息方面具有广泛应用.尽管前人利用SHG光谱或SHG显微成像方法探索研究了纳米线的精密定位或追踪问题,但是结合使用SHG光谱与SHG显微成像方法实现纳米材料结构与晶轴空间取向方面的研究鲜见报道.本研究分别使用SHG光谱与SHG显微成像方法研究了CdS纳米线空间取向问题.首先,基于全光学分析方法从实验上和理论上研究了硫化镉(CdS)纳米线SHG光谱强度随入射光偏振方向变化的规律,并详细分析了晶轴方位角γ,ω,φ对CdS纳米线SHG花型图的影响.其次,通过理论计算与实验测量结果相互验证,成功确定了单根CdS纳米线的3个晶轴取向.最后,利用偏振相关的SHG显微成像方法研究了单根CdS纳米线的空间取向,发现单根CdS纳米线不同部位具有不同的SHG响应.研究结果为SHG光谱与显微成像在纳米材料空间高精度定位研究提供了新的思路与重要参考,并为纳米材料在生物医学方面的潜在应用提供了重要启示.
The second harmonic generation(SHG),as a nonlinear optical effect,has a wide range of applications in obtaining information such as material composition,structure,and properties due to its good polarization sensitivity.Although SHG spectroscopy or SHG microscopy has been used to explore the precise positioning or tracking of nanowires,there are few reports on the combination of SHG spectroscopy and SHG microscopy to study the structure of nanomaterials and the spatial orientation of crystal axes.In this work,we investigate the spatial orientation and crystal axis orientation of cadmium sulfide(CdS)nanowires by combining SHG spectroscopy and microscopic imaging.Firstly,we experimentally and theoretically study the spectral intensity of the SHG of CdS nanowires with the polarization direction of the incident light based on the all-optical analysis method proposed by the predecessors.We also analyze the influence of the azimuth angle of the crystal axis g,ωand j on the pattern of the SHG of CdS nanowires in detail.Secondly,through the mutual verification of theoretical calculations and experimental measurement results,we successfully determine the three axial orientations of a single CdS nanowire.Finally,we also investigate the spatial orientation of a single CdS nanowire by using the polarization-dependent SHG microscopic imaging method.It is shown that different parts of the CdS nanowire have different SHG responses when the polarization is changed.These results provide a new idea and an important reference for studying the application of SHG spectroscopy and microscopic imaging in the research of high-precision spatial positioning of nanomaterials.This study provides important enlightenment for realizing the potential applications of nanomaterials in biomedicine.
作者
任立庆
杨强
姬超燃
池娇
胡云
魏迎春
许金友
Ren Li-Qing;Yang Qiang;Ji Chao-Ran;Chi Jiao;Hu Yun;Wei Ying-Chun;Xu Jin-You(Yulin Key Laboratory of High-Resolution Terahertz Vibrational Imaging,College of Energy Engineering,Yulin University,Yulin 719000,China;South China Academy of Advanced Optoelectronics,South China Normal University,Guangzhou 510006,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2024年第16期102-109,共8页
Acta Physica Sinica
基金
国家自然科学基金(批准号:12064046)
陕西省科技资源共享平台项目(批准号:2023-CX-PT-16)
陕西省青年创新团队项目(批准号:23JP202)资助的课题.
关键词
二次谐波产生
硫化镉纳米线
偏振
晶体取向
second harmonic generation
CdS nanowire
polarization
crystal orientation
