中国激光, 2015, 42 (4): 0406001, 网络出版: 2015-02-16
色散缺陷对Sinc函数型光子晶体带隙的影响
Effect of Dispersive Defect on Bandgap of One-Dimensional Sinc Function Photonic Crystals
材料 函数光子晶体 传输矩阵法 色散缺陷 光子带隙 materials function photonic crystal transfer-matrix method a dispersive defect photonic band-gap
摘要
利用传输矩阵法及对色散缺陷层采用洛伦兹振子模型,研究了一维含色散缺陷的Sinc 函数型光子晶体的光子禁带和色散缺陷模,计算了该周期结构的复有效折射率。结果表明,加入缺陷层后可获得宽阔的光子禁带;缺陷层引入色散后在中心圆频率附近色散缺陷模出现;随着振子强度的增大,增益性缺陷模圆频率发生阶跃式移动,其透射率显著增大,而吸收性缺陷模的透射率显著减小,此时缺陷模处的色散曲线有一个近乎垂直的斜率,此处的群速度将大大降低;增益性缺陷层基底折射率对缺陷模频率影响显著;缺陷层位于周期结构中心层时缺陷模频率最低、透射率最大。增大入射角使得缺陷模红移,增益性缺陷模在特殊入射角处透射率会出现千倍增益。
Abstract
By means of transfer matrix method, the photonic band-gap and the center tunneling mode of onedimensional Sinc function photonic crystal with dispersive defect are discussed. The dispersive defects are described by a Lorentz oscillator model. The complex effective index of the structure is calculated. It is found that an extremely wide photonic band gap is obtained after adding defect layer. After the introduction of the dispersion of the defect layer, the dispersive defect modes are appeared near the center angular frequency. With the increase of the oscillator strength, the angular frequency of the gain defect mode is stepped, the transmittance of them is significantly increased, but the transmittance of the absorptive defect mode is reduced, and the slope of a nearly vertical of dispersion curves is obtained at the angular frequency of the dispersive defect mode,group velocity here is greatly reduced. The angular frequency of the defect mode is significantly affected by the refractive index of the substrate of the gain defect layer. The angular frequency of the defect mode is the lowest and transmittance of them is the maximum when the defect layer is located in the center of the periodic structure. The angular frequency of the defect mode is made redshift with the increasing of the angle of incidence, and the transmittance of the gain defect mode is obtained thousands times in a special angle of incidence.
王筠. 色散缺陷对Sinc函数型光子晶体带隙的影响[J]. 中国激光, 2015, 42(4): 0406001. Wang Yun. Effect of Dispersive Defect on Bandgap of One-Dimensional Sinc Function Photonic Crystals[J]. Chinese Journal of Lasers, 2015, 42(4): 0406001.