Coupling characteristics of laterally coupled gratings with slots  

作　　者：Kun Tian Yonggang Zou Linlin Shi He Zhang Yingtian Xu Jie Fan Hui Tang Xiaohui Ma 田锟;邹永刚;石琳琳;张贺;徐英添;范杰;唐慧;马晓辉(State Key Laboratory on High Power Semiconductor Lasers,Changchun University of Science and Technology,Changchun 130022,China)

机构地区：[1]State Key Laboratory on High Power Semiconductor Lasers,Changchun University of Science and Technology,Changchun 130022,China

出　　处：《Chinese Physics B》2022年第11期352-357,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.61804013,61804014,and 61805023);Department of Science and Technology of Jilin Province,China(Grant Nos.20190302052GX and 20210201030GX)。

摘　　要：Laterally-coupled ridge-waveguide distributed feedback lasers fabricated without epitaxial regrowth steps have the advantages of process simplification and low cost.We present a laterally coupled grating with slots.The slots etched between the ridge and grating area are designed to suppress the lateral diffusion of carriers and to reduce the influence of the aspect-ratio-dependent-etching effect on the grating morphology in the etching process.Moreover,the grating height in this structure can be decreased to lower the aspect ratio significantly,which is advantageous over the conventional laterally coupled ridge waveguide gratings.The effects of five main structural parameters on the coupling characteristics of gratings are studied by MODE Solutions.It is found that varying the lateral width of the grating can be used as an effective way to tune the coupling strength;narrow slots(100 nm and 300 nm)and wide ridge(2μm–4μm)promote the stability of grating coupling coefficient and device performance.It is important to note that the grating bottom should be fabricated precisely.The comparative study of carrier distribution and mode field distribution shows that the introduction of narrow slots can strengthen the competitive advantage and stability of the fundamental mode.

关 键 词：Bragg gratings distributed feedback(DFB)lasers coupling coefficient mode field distribution 

分 类 号：TN248[电子电信—物理电子学]