线缺陷对二维四方圆柱形介质光子晶体禁带的影响

利用平面波展开方法研究了二维四方格子圆柱形介质光子晶体中线缺陷对光子禁带的影响.结果表明光子晶体中的缺陷层圆柱半径及缺陷层厚度对光子晶体禁带有显著影响.TE波的第一禁带宽度随着缺陷层半径的增加先增加后减小,禁带的中心位置随着缺陷层圆柱半径的增加而下降,禁带的数目也随着缺陷层圆柱半径的增加而明显变化.禁带的宽度随着缺陷层厚度与正常层厚度差别的增加而减小.

EFFECT OF LINE DEFECTS ON THE BAND OF TWO DIMENSIONAL SQUARE PHOTONIC CRYSTAL

The effect of line defects on photonic band gap was investigated for the two dimensional photonic crystal consisting of square lattices of dielectric cylinder by means of plane wave expansion method. The result shows that both the radius and the width of defect layer in photonic crystal have an obvious effect on photonic band gap. The first band gap width of the TE wave was a maximum with the increase of the radius of the defect cylinders. The centre of the band gap shifts down and the numbers of band gap are changed well with increase of the radius of the defect cylinders. In addition, the band gap width is reduced as the difference between the width of defect layer and that of normal layer increases.