On optical rotation and selective transmission in ambichiral sculptured   thin films
  The optical rotation and selective transmission spectrum of ambichiral sculptured thin films using transfer matrix method have been calculated. The results of optical modeling showed that optical characteristics ambichiral sculptured thin films are the same as chiral sculptured thin films in lower angular rotations. In higher angular rotations appear two circular Bragg regimes. The primary at shorter wavelengths reflects LCP light and the secondary at longer wavelengths reflects RCP light. The optical properties of ambichiral sculptured thin films with twist and layer defects as spectral holes in circular Bragg regimes have been reported. 
Ferydon Babaei
physics.optics physics.class-ph