supported by the National Natural Science Foundation of China (No. 60707010);the Natural Science Foundation of Chongqing (CSTC,2007BB3125)
A novel fiber Bragg grating (FBG) with two transmission dips in 1310- and 1550-nm regions is proposed and inscribed by an infrared femtosecond laser. Formed by multi-photon ionization, this type of grating can withs...