Computational and Experimental Analysis of Gold Nanorods in Terms of Their Morphology: Spectral Absorption and Local Field Enhancement

A nanoparticle’s shape and size determine its optical properties. Nanorods are nanoparticles that have double absorption bands associated to surface plasmon oscillations along their two main axes. In this work, we analize the optical response of gold nanorods with numerical simulations and spectral...

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Detalles Bibliográficos
Autores: Núñez Leyva, Juan Manuel, Kolosovas Machuca, Eleazar Samuel, Sánchez, John Eder, Guevara, Edgar, Cuadrado Conde, Alexander, Alda, Javier, González, Francisco Javier
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/8361
Acceso en línea:https://hdl.handle.net/20.500.14352/8361
Access Level:acceso abierto
Palabra clave:620.3
537.8
543.424.2
Computational electromagnetism
Gold nanorods
Raman spectroscopy
Electromagnetismo
Óptica (Física)
Partículas
2202 Electromagnetismo
2209.19 Óptica Física
2208 Nucleónica
Descripción
Sumario:A nanoparticle’s shape and size determine its optical properties. Nanorods are nanoparticles that have double absorption bands associated to surface plasmon oscillations along their two main axes. In this work, we analize the optical response of gold nanorods with numerical simulations and spectral absorption measurements to evaluate their local field enhancement—which is key for surface-enhanced Raman spectroscopic (SERS) applications. Our experimental results are in good agreement with finite element method (FEM) simulations for the spectral optical absorption of the nanoparticles. We also observed a strong dependence of the optical properties of gold nanorods on their geometrical dimension and shape. Our numerical simulations helped us reveal the importance of the nanorods’ morphology generated during the synthesis stage in the evaluation of absorption and local field enhancement. The application of these gold nanorods in surface-enhancement Raman spectroscopy is analyzed numerically, and results in a 5.8×104 amplification factor when comparing the values obtained for the nanorod deposited on a dielectric substrate compared to the nanorod immersed in water.