Planar chiral meta-materials for photonic devices

We report the first optical results due to the effects of two-dimensional (2D) chirality. Using electron beam lithography we have fabricated arrays of metallic planar chiral structures on dielectric substrates, with characteristic dimensions in the near infra-red, and observed the effects of their chirality on the polarization states of diffracted light. The results showed strong polarization effects, with the handedness of the individual elements having a direct effect on the sense and magnitude of rotation of the diffracted light. We believe such structures could, in the future, form the core of a new class of meta-materials with refractive indices engineered to suit individual optical applications.