Multiple metallic-shell nanocylinders for surface-enhanced spectroscopes

• Published in: Nanoscale research letters Vol. 6; no. 1; p. 173
• Main Authors: Lu, Jin-You, Chiu, Kuo-Pin, Chao, Husan-Yi, Chang, Yuan-Huei
• Format: Journal Article
• Language: English
• Published: New York Springer New York 24.02.2011; Springer Nature B.V; BioMed Central Ltd; Springer; SpringerOpen
• Subjects: Chemistry and Materials Science; International Conference on Superlattices; Materials Science; Molecular Medicine; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanostructures and Nanodevices (ICSNN 2010); Nanotechnology; Nanotechnology and Microengineering; Electric Field Intensity; Plasmon Mode; SERS; Cavity Mode; Resonance Wavelength
• ISSN: 1556-276X; 1931-7573; 1556-276X
• DOI: 10.1186/1556-276X-6-173

The optical properties of multiple dielectric-core-gold-shell nanocylinder pairs are investigated by two-dimensional finite difference time domain method. The core-shell cylinders are assumed to be of the same dimension and composition. For normal incidence, the diffraction spectra of multiple cylinder pairs contain the lightning-rod plasmon mode, and the electric field intensity is concentrated in the gap between the nanocylinder pairs in the infrared region. The resonance wavelength and local field enhancement of this plasmon mode can be tuned by varying the pair-distance between the pairs, the gap-distance between the pairs, and the optical constants of the dielectric-core and the surrounding medium. The results show that the multiple core-shell nanocylinder pair contains the plasmon mode same as that of the solid metallic cylinder pairs at the long wavelength part of the spectrum. The large electric field intensity in the infrared region at long wavelength makes multiple core-shell cylinders as ideal candidates for surface-enhanced spectroscopes.