Optical chirality: conservation law in arbitrary space
- The introduction of the near-field quantity of optical chirality has emerged in various numerical and few experimental studies of local chirality enhancement due to its relation to the excitation rate of chiral molecules. This time-even pseudoscalar has been dismissed as being a higher-order version of helicity. Nevertheless, we revisit the derivation of the underlying conservation law and define optical chirality in media similar to. We identify the mechanism of chirality conversion by either inhomogeneous or anisotropic space to complement the conservation of optical chirality. The conservation law of optical chirality in arbitrary space enables the extension of the concept of polarization to the near-field where no distiniguished propagation direction of light is present. We show that the connection of electromagnetic energy and optical chirality provide the ability to define a circular polarization basis in time-harmonic near-field analysis. In order to illustrate our theory, we present electromagnetic field simulations of simple as well as more complex nanostructures. Results using the well-known far-field polarization concept are readily reproduced and extended from the point of view of chirality conversion.
Author: | Philipp Gutsche, Lisa Poulikakos, Sven BurgerORCiD, Martin Hammerschmidt, Frank Schmidt |
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Document Type: | Poster |
Parent Title (English): | 606. WE-Heraeus-Seminar on Nanophotonics and Complex Spatial Modes of Light |
Year of first publication: | 2016 |