1. Surface plasmons excited by multiple layer grating
- Author
-
Chun-Hway Hsueh, Chang-Lin Wu, and Jia-Han Li
- Subjects
Total internal reflection ,Materials science ,business.industry ,Surface plasmon ,Physics::Optics ,02 engineering and technology ,Grating ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surface plasmon polariton ,Atomic and Molecular Physics, and Optics ,010309 optics ,Optics ,Electric field ,0103 physical sciences ,Physics::Atomic Physics ,Thin film ,0210 nano-technology ,business ,Layer (electronics) ,Electron-beam lithography - Abstract
The surface plasmons that are excited by the multiple layer grating structures on the gold thin film are studied using the finite-difference time-domain method in this paper. The structure parameters’ effects on the coupling enhancement of surface plasmons are examined, and the structure design guidelines are given. It is found that the distance between the grating layers and the distance between the gratings and gold thin film are the key structure parameters for better cavity resonances. To have the stronger field enhancements of the excited surface plasmons for the multilayer grating structures, it is found that the width of the gratings should be smaller for the lower grating layers. The multiple layer gratings with proper structure designs can have better performances than single layer grating structure because the cavity effects can enhance the light coupling and more light can be coupled into the surface plasmons by more layers of grating. It is found that the maximum electric field intensity for five layer grating structures can be 163% of the case of the single layer grating structure in our simulations.
- Published
- 2019