Helicity preserved scattering in colloidal silicon nanoparticles

Abstract

"Dual" nanoparticles, which have electromagnetic duality and respond equally to the electric and magnetic fields of light, the helicity of scattered light is preserved in all directions, and a circularly polarized near field (super-chiral field) is formed around the nanoparticle. The super-chiral field is expected to enhance the circular dichroism of chiral molecules. In this article, we show that crystalline and spherical silicon nanoparticles with a diameter of 100 to 200 nm, which have low-order Mie resonances in the visible to near-infrared wavelength range, behave as "dual" nanoantennas at specific wavelengths. Furthermore, we experimentally demonstrate the helicity preserved scattering in colloidal dispersion of silicon nanoparticles developed by the authors.