柱体截面不同三角晶格二维光子晶体完全带隙的研究

Study on the Complete Photonic Bandgap in Two-Dimensional Triangular Lattice Photonic Crystal Composed of Different Section Poles

采用平面波展开法(PWM),研究以Ge为背景的空气柱构成的三角形结构二维光子晶体的带隙结构,考虑空气柱截面为圆形和六边形2种情况.结果表明:在介电常数和晶格常数不变的情况下,前者比后者更容易形成完全带隙,并且带隙宽度和相对带隙宽度也较大,前者完全带隙的最大宽度是后者的2.4倍,最大相对带隙宽度是后者的4倍.

The bandgap structure of two - dimensional triangular structure photonic crystal composed of air rods in Ge -dielectric is calculated with the plan wave expansion method. With the circular section pole and the hexagonal section pole taken into consideration, the results indicate that the former structure is easy to form the complete bandgap than the latter in case of fixedness in dielectric constant and crystal lattice constant, and the size of the complete bandgap and that of the relative complete bandgap are also larger. The results also show that the size of the complete bandgap in the former structure is almost 2.4 times as large as the latter and the size of the relative complete bandgap is 4 times as large as the latter.