학술논문

Strain effects on the SERS enhancements for spherical silver nanoparticles.
Document Type
Article
Source
Nanotechnology. Sep2010, Vol. 21 Issue 36, p365704-365704. 1p.
Subject
*NANOPARTICLES
*OPTICAL properties
*SILVER compounds
*RAMAN spectroscopy
*DEFORMATIONS (Mechanics)
*STRAINS & stresses (Mechanics)
*SURFACE plasmon resonance
Language
ISSN
0957-4484
Abstract
We demonstrate in the present work through the utilization of classical Mie scattering theory in conjunction with a radiation damping and dynamic depolarization-corrected electrostatic approximation the significant effect that mechanical strain has on the optical properties of spherical silver nanoparticles. Through appropriate modifications of the bulk dielectric functions, we find that the application of tensile strain generates significant enhancements in the local electric field for the silver nanoparticles, leading to large SERS enhancements of more than 300% compared to bulk, unstrained nanoparticles when a 5% tensile strain is applied. While the strain-induced SERS enhancements are found to be strongest for nanoparticle diameters where radiation damping effects are minimized, we find that the surface plasmon resonance wavelengths are relatively unchanged by mechanical strain, and that the various measures of the far field optical efficiencies (absorption, scattering, extinction) can be enhanced by up to 150% through the application of tensile strain. The present findings indicate the opportunity to actively engineer and enhance the optical properties of silver nanoparticles through the application of mechanical deformation. [ABSTRACT FROM AUTHOR]