摘要
介绍了一种低串扰、频谱响应平坦化的刻蚀衍射光栅 (EDG)解复用器的机理与设计方法 ,设计带有预整形输入的优化的多模干涉 (MMI)结构 .该设计采用了广角束传播方法 (BPM)、基耳霍夫衍射理论以及模式传输理论等方法 .给出一个优化的预整形渐变波导结构 ,以获得更陡的输出场边缘 ,使用 MMI结构 ,获得了平坦的频谱响应 ,设计结构还获得了相对较低的色散值 .
A flat-topped planar waveguide demultiplexer with low crosstalk is designed.A multimode interference (MMI) section with a reshaping taper is connected at the end of the input waveguide.An etched diffraction grating (EDG) demultiplexer is considered as a design example.A wide-angle beam propagation method (BPM),the Kirchhoff diffraction theory,and the mode propagation analysis are used in the simulation.The field distribution at the end of the taper is reshaped optimally to have sharp transitions.The designed EDG demultiplexer has an excellent flat-topped spectral response and a very low crosstalk,and a low chromatic dispersion characteristic.
基金
浙江省科技计划资助项目 (编号 :0 0 110 10 2 7)~~
关键词
刻蚀衍射光栅
频谱平坦化
串扰
色散
etched diffraction grating
flattened spectral response
crosstalk
chromatic dispersion
