Liu Xiao, Zhang Meiling, Hu Guijun
Department of Communication Engineering, Jilin University, Changchun 130012, China.
Nanomaterials (Basel). 2022 Aug 25;12(17):2937. doi: 10.3390/nano12172937.
A SiN slot waveguide has the ability to confine light tightly in the slot, shows weak absorption of 980 nm pump light, and has lower transmission loss compared to a Si slot. Hence, the optical waveguide amplifier based on Er and Ybcodoped was proposed to be integrated with a SiN slot to increase the gain. The core-shell NaYF/NaLuF: 20%Yb, 2%Er nanocrystals-polymeric methyl methacrylate covalent linking nanocomposites were synthesized and filled into the slot as gain medium. The concentrations of Er and Yb were increased compared with traditional physical doping methods. High-efficiency emission at 1.53 μm was achieved under 980 nm laser excitation. The slot waveguide was accurately designed using the semivector finite difference method in combination with the maximum confinement factors and the minimum effective mode area. The optimum width of the slot was 200 nm, and the optimum height and width of the silicon strip waveguide were 400 nm and 400 nm, respectively. The six-level spectroscopic model was presented, and the gain characteristics of the slot waveguide amplifier were numerically simulated. A net gain of 8.2 dB was achieved, which provided new ideas and directions for waveguide amplifiers.
氮化硅槽型波导能够将光紧密限制在槽中，对980nm泵浦光的吸收较弱，并且与硅槽相比具有更低的传输损耗。因此，提出将基于铒和镱共掺杂的光波导放大器与氮化硅槽集成以提高增益。合成了核壳结构的NaYF/NaLuF:20%Yb,2%Er纳米晶体-聚甲基丙烯酸甲酯共价连接纳米复合材料，并将其填充到槽中作为增益介质。与传统的物理掺杂方法相比，铒和镱的浓度有所提高。在980nm激光激发下实现了1.53μm的高效发射。结合最大限制因子和最小有效模式面积，采用半矢量有限差分法精确设计了槽型波导。槽的最佳宽度为200nm，硅条形波导的最佳高度和宽度分别为400nm和400nm。提出了六级光谱模型，并对槽型波导放大器的增益特性进行了数值模拟。实现了8.2dB的净增益，为波导放大器提供了新的思路和方向。
