Electrically tunable omnidirectional photonic bandgap in one-dimensional photonic crystal with nonlinear composite materials and metamaterials

It is well known that the omnidirectional photonic bandgap (zero-n bandgap) can be realized in the one-dimensional photonic crystals containing metamaterials. However, these omnidirectional photonic bandgaps are not tunable. In this manuscript, we show that the electrically tunable omnidirectional photonic bandgap can be obtained in one-dimensional photonic crystal with third-order nonlinear composite materials and linear metamaterials. It is demonstrated this photonic crystal possesses electrically tunable photonic band structures based on the fact that the effective refractive index of nonlinear composite material has electric-field dependence due to the existence of third-order nonlinear responses. Moreover, we also showed that the photonic bandgap of this photonic crystal can be tuned by controlling the filling fraction f of the composite.