State Key Laboratory of Modern Optical Instrumentation, Department of Optical Engineering, Zhejiang University, Hangzhou 310027, China.
Opt Lett. 2011 Aug 15;36(16):3115-7. doi: 10.1364/OL.36.003115.
We fabricate fiber Bragg grating (FBG) in microfibers (MFs) using focused ion beam milling technique. By periodically etching 100 nm-depth grooves on the surface of silica MFs with diameters less than 2 μm, evident grating features with transmission dip up to 15 dB are obtained. Because of the high-index contrast of the gratings structure, the length of the microfiber Bragg grating (MFBG) can be reduced to 500 μm level. Using a 518 μm-length 1.8 μm-diameter MFBG, we also demonstrate sensitivity up to 660 nm per refractive index unit (RIU) for refractive index (RI) sensing. The highly compact MFBGs demonstrated here may serve as low-dimensional building blocks for miniaturized photonic components and devices.
我们使用聚焦离子束铣削技术在微纤维（MFs）中制造光纤布拉格光栅（FBG）。通过周期性地在直径小于 2 μm 的二氧化硅 MF 表面刻蚀 100nm 深的凹槽，获得了具有高达 15dB 传输损耗的明显光栅特征。由于光栅结构的高折射率对比度，可以将微光纤布拉格光栅（MFBG）的长度缩短到 500μm 水平。使用长度为 518μm、直径为 1.8μm 的 MFBG，我们还证明了其折射率（RI）传感的灵敏度高达每折射率单位（RIU）660nm。这里展示的高紧凑 MFBG 可以作为小型化光子组件和器件的低维构建块。
