We analyze the effect of contaminants on the quadrupolar magnetic, dipolar electric and dipolar magnetic resonances of silicon nanoparticles (NPs) by considering the spectral evolution of the linear polarization degree at right angle scattering configuration, P_L(90°). From an optical point of view, a decrease in the purity of silicon nanoparticles due to the presence of contaminants impacts the NP effective refractive index. We study this effect for a silicon nanosphere of radius 200 nm embedded in different media. The weakness of the resonances induced on the P_L(90°) spectrum because of the lack of purity can be used to quantify the contamination of the material. In addition, it is shown that Kerker conditions also suffer from a spectral shift, which is quantified as a function of material purity.

Date Published: 29 April 2016
PDF: 8 pages
Proc. SPIE 9899, Optical Sensing and Detection IV, 98991O (29 April 2016); doi: 10.1117/12.2227774

Published in SPIE Proceedings Vol. 9899:
Optical Sensing and Detection IV
Francis Berghmans; Anna G. Mignani, Editor(s)