One-dimensional anisotropic photonic crystal with a tunable bandgap

A one-dimensional anisotropic photonic crystal, which consists of alternating layers of an anisotropic and isotropic media, is studied by solving Maxwell's equations using the plane-wave method. For on-axis propagation in such a one-dimensional photonic crystal, the allowed two polarizations in the anisotropic medium will experience different refractive indices and thus the degeneracy in the photonic band structure disappears. Bandgap tuning based on a liquid crystal and the Pockel effect has been investigated. For a liquid-crystal infiltrated one-dimensional photonic crystal, it is shown how the optic axis orientation of the liquid crystal affects the bandgap. The effect of rotation of the principal axes caused by an external electric field to the electro-optic tunability of the photonic crystal made of Pockel materials is also analyzed.