论文部分内容阅读
亚波长光栅具有特殊的反射特性,可以用于各种光器件的设计。利用时域有限差分方法(FDTD)和散射矩阵方法计算了亚波长介质光栅的能带结构、本征模式以及反射谱。模拟结果显示:光栅反射谱中的共振峰是由光栅的泄漏模式引起的;在正入射和斜入射条件下,外部入射场所能激励的光栅的模式不同;通过控制光栅本征泄漏模的频率和Q值可以控制反射谱线型。实验利用电子束直写以及反应离子刻蚀等方法在绝缘体上硅(SOI)晶圆上制备出亚波长光栅结构,实验测量所得光栅的反射谱线型与模拟结果吻合得很好。
Sub-wavelength grating has a special reflection characteristics, can be used for a variety of optical device design. The energy band structure, eigenmode and reflection spectra of sub-wavelength dielectric gratings are calculated by FDTD method and scattering matrix method. The simulation results show that the resonance peak in the grating reflection spectrum is caused by the grating leakage mode. Under the normal incident and oblique incidence conditions, the modes of the grating that can be excited by external incident sites are different. By controlling the frequency of the grating intrinsic leakage mode and Q value can control the reflection spectrum line type. Experiments using electron beam direct writing and reactive ion etching and other methods on the silicon on insulator (SOI) wafer prepared sub-wavelength grating structure, experimental measurement of the grating reflection spectrum line with the simulation results are in good agreement.