二维光子晶体层状超晶格透射特性研究

把平面波展开法(Plane Wave Expansion Method,PWM)用于数值研究圆柱柱体粗细及折射率层状间隔构成的二维光子晶体超晶格的传输特性.数值结果表明,层状超晶格的透射谱中禁带宽度在柱体折射率相同时与粗细柱体半径差异成线性关系,半径相差越大禁带宽度越小,禁带中心位置越向低频方向移动.在半径相同时禁带宽度与层间折射率差异同样成线性关系,折射率相差越大禁带宽度越小,禁带中心位置越向低频方向移动.因此人们可以根据实际应用中的禁带需要利用上述各种可调因素进行调节.

Research on Transmission Spectra of Superlattice with Multilayer Two-Dimensional Photonic Crystal

The superlattice transmission spectra characteristics of two-dimensionl cylindrical photonic crystals formed by layers with different diameters of cylinders and refractive index are numerically studied using plane wave expansion method (PWM). The results indicate that the forbidden band of layer superlattice transmission spectrum show linear relationship (behavior) with the difference between thick and thin cylinder radius for same cylinder refractive index. The greater the difference between thick and thin cylinder radius, the smaller the width of the forbidden band, and the central position of forbidden band moves towards low-frequency more. For same cylinder radius, the width of forbidden band also shows linear relationship (behavior) with the difference of the layer refractive index. The greater the difference of the layer refractive index, the smaller the width of forbidden band, and the central position of forbidden band moves towards low-frequency more. Therefore, it can use the above adjustable factors to attain the adjustive purpose according to the forbidden band needs in practical application.