Li Keke, Liu Anping, Wei Dapeng, Yu Keke, Sun Xiaonan, Yan Sheng, Huang Yingzhou
Department of Applied Physics, College of Physics, Chongqing University, Chongqing, 400044, China.
Soft Matter and Interdisciplinary Research Center, College of Physics, Chongqing University, Chongqing, 400044, China.
Nanoscale Res Lett. 2018 Apr 25;13(1):124. doi: 10.1186/s11671-018-2535-0.
Benefiting from the induced image charge on metal film, the light energy is confined on a film surface under metal nanoparticle dimer, which is called electromagnetic field redistribution. In this work, electromagnetic field distribution of metal nanoparticle monomer or dimer on graphene is investigated through finite-difference time-domain method. The results point out that the electromagnetic field (EM) redistribution occurs in this nanoparticle/graphene hybrid system at infrared region where light energy could also be confined on a monolayer graphene surface. Surface charge distribution was analyzed using finite element analysis, and surface-enhanced Raman spectrum (SERS) was utilized to verify this phenomenon. Furthermore, the data about dielectric nanoparticle on monolayer graphene demonstrate this EM redistribution is attributed to strong coupling between light-excited surface charge on monolayer graphene and graphene plasmon-induced image charge on dielectric nanoparticle surface. Our work extends the knowledge of monolayer graphene plasmon, which has a wide range of applications in monolayer graphene-related film.
得益于金属薄膜上感应出的镜像电荷，光能被限制在金属纳米颗粒二聚体下方的薄膜表面，这被称为电磁场重新分布。在这项工作中，通过时域有限差分法研究了石墨烯上金属纳米颗粒单体或二聚体的电磁场分布。结果表明，在该纳米颗粒/石墨烯混合体系的红外区域发生了电磁场（EM）重新分布，在此区域光能也可被限制在单层石墨烯表面。使用有限元分析对表面电荷分布进行了分析，并利用表面增强拉曼光谱（SERS）对这一现象进行了验证。此外，关于单层石墨烯上介电纳米颗粒的数据表明，这种EM重新分布归因于单层石墨烯上光激发表面电荷与介电纳米颗粒表面石墨烯等离子体激元诱导的镜像电荷之间的强耦合。我们的工作扩展了单层石墨烯等离子体激元的知识，其在单层石墨烯相关薄膜中具有广泛的应用。
