Abstract :
Dispersion properties of two types of three-dimensional (3D) nomagnetized plasma photonic crystals (PPCs) with face-centered-cubic lattices have been investigated by a modified plane wave expansion (PWE) method. The first type (type-1) is a 3D PPCs which dielectric spheres are arranged in the plasma background periodically with face-centered-cubic lattices, while the second one (type-2) is a complementary structure composed of plasma spheres in the dielectric background. It is found that a flatbands region and two stop gaps appear in Γ–X and Γ–L directions, respectively. The results show that the upper edges of flatbands regions for both types of PPCs cannot be tuned except for plasma frequency. The stop gaps in Γ–X and Γ–L directions for both types of PPCs can be modulated by the filling factor, relative dielectric constant and plasma frequency, respectively. However, the plasma collision frequency has no effect on the locations of stop gaps in Γ–X and Γ–L directions, and also cannot control the upper edges of flatbands regions for both types of PPCs. The results may provide theoretical foundations to design the new tunable photonic crystals devices in microwave communications.
