二维介质柱型阿基米德复式晶格光子晶体禁带特性

he bandgaps of the two-dimensional Archimedes (4，82) lattice consisting of different dielectric circular and square rods are calculated with the plane wave expansion method. The bandgaps of the lattice with dielectric rods are also investigated as the refractive index, dielectric rods shape, filling fraction and rotational symmetry changing. it was found that complete photonic bandgaps can be achieved in the (4，82) structure when the refractive index is between 2.60 and 5.40. For the Archimedes (4，82) lattice of circular dielectric rod, the width of complete bandgap reaches the maximum at the dielectric refractive index of rod is equal to 2.80. Also, the complete bandgap of square dielectric rod reaches the maximum when the dielectric refractive index equals 2.80 or 4.40. in addition, the rotation angle of square dielectric rods can significantly increase the width of complete bandgap. The results demonstrate that the quantity, width and frequency position of bandgaps can be modulated by changing the refractive index, the filling fraction and other structural parameters.