Asymmetric diffraction from regular, quasi-random fractal planar chiral nanostructures

Planar chiral structures are an intriguing new type of optical meta-material which offer the possibility of effective manipulation of the polarization state of light in the far and near fields, as well as manifesting a range of new phenomena such as 2D optical activity. They also promise intriguing new properties such as nonreciprocal diffraction and time non-reversal light scattering. In addition, we have developed a new continuous chirality measure and, for the first time, simultaneously evaluated the chirality of diffraction gratings and of the corresponding field distribution of light diffracted from them. We also define symmetry groups for both the arrays and their corresponding diffraction patterns. The experimental results are compared with computer simulations of scattered field