Electromagnetic wave propagation in Twist Grain Boundary phases

The propagation of electromagnetic waves within Twist Grain Boundary sample s are theoretically considered. Fully analytical expressions for light prop agating along the superstructure helix axis are given. The optical properti es for oblique light are studied numerically. Moreover, an homogeneous mode l is developed for pitch shorter than the wavelength in order to describe t he natural optical activity. The possibility to obtain the material paramet ers by optical methods is discussed.