提出一种氮化镓与掺偶氮苯聚合物复合材料集成光波导光栅耦合器,并通过仿真计算分析了这种器件的特性。用氮化镓铝衬底上对称的双氮化镓脊形光波导构成集成光波导定向耦合器,涂覆掺偶氮苯聚甲基丙烯酸甲酯聚合物作为包层。利用掺偶氮苯聚合物的光敏特性,在两脊形波导间区域通过周期性光照制作布拉格光栅。利用耦合模理论分析了这种光栅耦合器中各模式间的耦合关系,确定了各模式的耦合模方程,仿真计算了这种光栅耦合器各端口的输出特性,包括各模式的幅度随着传输距离的变化,以及各端口输出的幅度变化关系。在此基础上进一步分析了多周期耦合光栅耦合器的频谱特性,为集成光路中实现复杂频谱信号的操作提供了一种新的实现方案。

An integrated optical waveguide grating coupler using gallium nitride and azobenzene polymer composites is designed, and the characteristics of the device are analyzed by simulation. An integrated optical waveguide directional coupler is constructed using two symmetric gallium nitride ridge optical waveguides on a gallium nitride aluminum substrate, and an azobenzene-containing polymethyl methacrylate polymer is coated as a cladding. Based on the photosensitive properties of the azobenzene polymer, a Bragg grating is fabricated by periodic illumination in the region between the two ridge waveguides. The coupling between the modes in the grating coupler is analyzed by the coupled mode theory. Using the coupled mode equations, the output characteristics of each port of the grating coupler are simulated, including the output of each mode as a function of the transmission distance and the amplitude variation under different coupling period conditions. The spectral characteristics of the multi-coupling-period grating coupler are further analyzed, which provides a new scheme for realizing the operation of complex spectrum signal in integrated optical path.