Correlation Between Surface Charge Distribution and Circular Dichroism of Elementary Planar Nanoparticles

Abstract

A correlation is observed between surface charge distributions and the circular dichroism (CD) signature of nanoparticles excited by circularly polarized waves. These surface charge distributions arise as a result of charge separation and depend on the polarization of the externally excited light. This correlation can be observed by deriving the surface charge distribution profile of excited localized surface plasmon polaritons (SPPs) in elementary metal nanoparticles under the influence of circularly polarized light. Nanoparticles with strong CD signatures are especially desired for sensing of chiral biomolecules as well as to aid in photochemical catalysis. We also found out that CD signatures can even be induced via angular rotation. This is true for elementary non-rotated nanoparticles which do not possess a CD signature. The use of elementary nanoparticles for sensing poses a huge advantage over complex nanostructures due to the ease of fabrication. The observed CD signature can also be validated in accordance with theory and simulation results.