Cylindrical fiber cored by a double twisted chiral nematic

We consider an electromagnetic field propagating within a waveguide consisting of a material having double helix, as those found in some chiral nematic materials such as blue phases, which lies along the axis of the fiber. We establish the electromagnetic equation governing the dynamics of the propagating modes and solve them numerically. We found the band structure of the mentioned modes, the profiles field amplitudes and the Poynting vector distributions versus the radius of the fiber. We discuss the composition and conditions fo rthis modes to propagate,