Reversal of Circular Bragg Phenomenon in Ferrocholesteric Materials with   Negative Real Permittivities and Permeabilities
  A structurally right/left-handed ferrocholesteric slab with negative real permittivities and permeabilities is theoretically shown to display the Bragg phenomenon on axial excitation as if it were a structurally left/right-handed ferrocholesteric slab with positive real permittivities and positive real permeabilities. In addition to the promise of isotropic homogeneous materials with negative real permittivities and permeabilities for unexpected applications, the presented results underscore the similar potential of anisotropic nonhomogeneous materials with analogous characteristics. 
Akhlesh Lakhtakia