Sensitivity analysis for characterization of gold nanoparticles and agglomerates via surface plasmon scattering patterns

A sensitivity analysis is performed to determine the optimum conditions for characterization of gold nanoparticles and agglomerates via surface plasmon scattering. Sensitivity of the normalized scattering matrix elements, M-ij, to different physical parameters are determined, including particle diameter, particle-surface distance, and particle agglomeration. The results, are reported as a function of the observation angle in the far-field, show that profiles Of M-12, M-33, and M-34 within certain range of angles are very sensitive to physical parameters of interest and can provide satisfactory characterization of nanosize particles. More specifically, the normalized scattering element M33, for observation angles between 110 degrees and 150 degrees in the far-field, is found to be sensitive enough to determine all the parameters investigated in this paper. These findings show, at least theoretically, the feasibility of characterization of gold nanoparticles and agglomerates via evanescent waves/ surface plasmons scattering patterns. (C) 2007 Elsevier Ltd. All rights reserved.