Bhardwaj Saurabh, Fernandez Toney Teddy, Gross Simon, Withford Michael J, Steel Michael J
Opt Lett. 2022 Feb 1;47(3):453-456. doi: 10.1364/OL.441813.
We investigate the morphology of femtosecond laser, single pulse-inscribed, point-by-point (PbP) fiber Bragg gratings. Direct measurement of a PbP grating's refractive index profile was carried out with micro-reflectivity analysis. PbP gratings were imaged at sub-micrometer scale with scanning electron microscopy, Raman and photoluminescence studies were performed to probe the structural and electronic changes. Comparison of results from different characterisation techniques suggests that the creation of an increased refractive index region around the micro-void is due to contributions from both densification and the formation of highly polarizable non-bridging oxygen bonds.
我们研究了飞秒激光逐点写入的光纤布拉格光栅的形态。通过微反射率分析对逐点光栅的折射率分布进行了直接测量。利用扫描电子显微镜在亚微米尺度下对逐点光栅进行成像，进行拉曼和光致发光研究以探测结构和电子变化。不同表征技术的结果比较表明，微空洞周围折射率增加区域的形成是由于致密化和高极化性非桥连氧键形成的共同作用。
