2015/08/31 by Ivan Fernandez-Corbaton, Martin Fruhnert, Carten Rockstuhl · 1 citation
Physics and Astronomy · #physics.optics
paper · pdf · doi:10.1103/physrevx.6.031013
published as Phys. Rev. X 6, 031013 (2016) · This version contains an example of how to use the theoretically derived constraints for designing realistic structures. It also contains a discussion related to the optical chirality density
arxiv created 2016/07/28 · arxiv updated 2016/08/03
We introduce a definition of the electromagnetic chirality of an object and show that it has an upper bound. Reciprocal objects attain the upper bound if and only if they are transparent for all the fields of one polarization handedness (helicity). Additionally, electromagnetic duality symmetry, i.e., helicity preservation upon interaction, turns out to be a necessary condition for reciprocal objects to attain the upper bound. We use these results to provide requirements for the design of such extremal objects. The requirements can be formulated as constraints on the polarizability tensors for dipolar objects or on the material constitutive relations for continuous media. We also outline two applications for objects of maximum electromagnetic chirality: a twofold resonantly enhanced and background-free circular dichroism measurement setup, and angle-independent helicity filtering glasses. Finally, we use the theoretically obtained requirements to guide the design of a specific structure, which we then analyze numerically and discuss its performance with respect to maximal electromagnetic chirality.