激光与光电子学进展, 2018, 55 (4): 042601, 网络出版: 2018-09-11
金属纳米表面等离子激元的共振辐射增强研究 下载: 1203次
Resonance Radiation Enhancement of Metal Nanometer Surface Plasmons
物理光学 辐射增强 Purcell效应 表面等离子激元 金属纳米颗粒 局域场 核壳结构 physical optics radiation enhancement Purcell effect surface plasmons metal nanoparticle local field core-shell structure
摘要
主要研究了不同结构参数对金属纳米表面等离子激元辐射增强的影响,以提高入射电磁波与金属表面自由电子的耦合效率。对Au、Ag纳米颗粒进行了数值模拟,比较了不同形状金属纳米颗粒的局域场增强。与其他结构相比,球形金属纳米颗粒具有更显著的局域场增强效应。通过改变球形金属纳米颗粒的各个参数进行Purcell分析,结果表明:沿极化方向的长轴尺寸、垂直于极化方向的短轴尺寸、环境材料的折射率以及光源距纳米颗粒的距离都会极大地改变金属纳米表面等离子激元共振辐射增强的效果,且会对共振波长的位置产生极大影响。最后对具有椭球壳结构的金属纳米颗粒进行了模拟,发现随着椭球壳内填充介质的折射率和椭球壳厚度改变,辐射强度都表现出不同程度的增强。
Abstract
In this paper, the influences of different structural parameters on the radiation enhancement of metal nanometer surface plasmons are studied to increase the coupling efficiency of the incident electromagnetic wave and the free electron of metal surface. The numerical simulation of Au and Ag nanoparticles is carried out, the local field enhancement of metal nanoparticles with different shapes are compared, the spherical metal nanoparticles have more prominent local field enhancement effect compared to other structures. Therefore, Purcell analysis is carried out by the change of the parameters of spherical metal nanoparticles. The results show that the size of long axis along the polarization direction, the size of short axis perpendicular to polarization direction, refractive index of environment materials as well as the distance of nanoparticles apart from the light source can greatly change the effect of metal nanometer surface plasmons resonance radiation enhancement, and they have great influence on the location of the resonance wavelength. Finally, the metal nanoparticles with ellipsoid shell structure are simulated. It is found that as the change of refractive index of the filling medium and the nuclear shell thickness, the radiation intensities are increased in different degrees.
马光辉, 于贺, 刘宇乾, 张贺, 金亮, 徐英添. 金属纳米表面等离子激元的共振辐射增强研究[J]. 激光与光电子学进展, 2018, 55(4): 042601. Guanghui Ma, He Yu, Yuqian Liu, He Zhang, Liang Jin, Yingtian Xu. Resonance Radiation Enhancement of Metal Nanometer Surface Plasmons[J]. Laser & Optoelectronics Progress, 2018, 55(4): 042601.