The influence of the degree of purity of a silicon nanoparticle on its resonances, either electric or magnetic, is assessed by using Mie theory as well as finite-element simulations. In particular, it is shown that the main effect of the increase of absorption due to the pollutants is observed in the magnetic resonances. Concerning Kerker’s conditions for the directionality of the scattering [J. Opt. Soc. Am. 73, 765 (1983)], it is found that both are strongly shifted when the material’s purity is varied. Resistive losses confirm the quenching of magnetic resonances, showing that the region of influence in the magnetic dipole resonance is much larger than in the electric one, although it has been found that losses are not critical for silicon content over 99.50%.
© 2014 Optical Society of America
Original Manuscript: February 27, 2014
Revised Manuscript: April 15, 2014
Manuscript Accepted: April 15, 2014
Published: May 20, 2014
J. M. Sanz, R. Alcaraz de la Osa, A. I. Barreda, J. M. Saiz, F. González, and F. Moreno, "Influence of pollutants in the magneto-dielectric response of silicon nanoparticles," Opt. Lett. 39, 3142-3144 (2014)