Hollow and filled fiber bragg gratings in nano-bore optical fibers
Zhang Yong-Xin1, Liang Sheng1, ‡, Yu Qian-Qing2, 3, Lian Zheng-Gang2, Dong Zi-Nian1, Wang Xuan1, Lin Yu-Qin1, Zou Yu-Qi1, Xing Kun1, Liang Liu-Yan1, Zhao Xiao-Ting4, Tu Li-Jing4
       

Reflected spectra of filled FBG and fundamental mode field of NBF with different bore diameters and fillings.