Spatial filtering by using cascading plasmonic gratings.
In this study, the optical properties of a plasmonic multilayer structure, consisting of two longitudinally cascaded gratings with a half pitch off-set, are investigated. The proposed structure, which is a system mixing extended and localized surface plasmon, forms transversely cascaded metal/insulator/metal cavities. The angle dependent reflection spectrum of the proposed structure displays a resonance peak at a specific angle. The full-width at half maximum (FWHM) of the resonant peak is smaller than 3 degrees. The angular dispersion of the cascading plasmonic gratings is about d theta/d lambda =0.15 degrees/nm. The cascading plasmonic gratings can be used as a spatial filter to improve the spatial coherence of a light source.
Institute of Opto-electronic Engineering, National Dong Hwa University, Hualien, Taiwan 97401, ROC. wangcm@mail.ndhu.edu.tw
Chih-Ming
CM
Wang
Yia-Chung
YC
Chang
Din Ping
DP
Tsai
D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005374:Filtration / Q000295:instrumentation*; D008027:Light; D008962:Models, Theoretical; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity