Femtosecond Laser Inscription of Long-Period Fiber Gratings in a Polarization-Maintaining Fiber

The method of femtosecond laser inscription by slit-apertured beam is applied for fabrication of long-period fiber gratings in polarization-maintaining Panda-type fiber. Polarization properties as well as ambient refractive index sensitivity are investigated for the inscribed gratings. It is shown that the method allows us to create high-quality element for the use as spectral filter of high-power fiber laser as well as high-temperature sensor.