Numerical and experimental analysis of long period gratings in wavelength scale elliptical microfibers

Jin Wa^{1, 2, †}, Bi Wei-Hong^{1, 2}, Fu Guang-Wei^{1, 2}

(color online) (a) Schematic diagram of the femtosecond laser system for fabricating LPGs in elliptical micro/nanofibers. (b) Transmission spectrums of an LPG with a pitch fabricated with a femtosecond infrared laser.