Chiral Properties of Light in Material Systems

Motivated by recent theoretical results concerning dynamical properties of light in dispersive and lossless media, here we address an alternative derivation for the optical chirality, extending it so as to include dissipative effects as well. Looking into the underlying mathematical structure of the continuity equation, we find a new general expression for the optical chirality density in dispersive and lossy media. In spectral regions with high absorption and anomalous dispersion, we observe important deviations in comparison with the lossless case. This fact should be carefully accounted for and examined when analyzing the optical chirality and its interaction with matter, mainly in the context of highly dispersive systems such as plasmonic nanostructures and metamaterials, whose chiral properties are receiving strong attention.