Study on polarization spectrum and annealing properties of 45°-tilted fiber gratings
We have investigated the whole polarization-extinction-ratio (PER) spectrum and annealing properties of 45°-tilted fiber gratings (45°-TFGs). Experimental results show the PER spectrum of 45°-TFGs is Gaussian-like profile and covers 540nm bandwidth form 1260 to 1800nm, in which the bandwidth with PER greater than 10dB is over 250nm. The output polarization distribution of 45°-TFGs was analyzed by employing a bulk linear polarizer, and the results show a perfect figure “8”, which indicates that the 45°-TFG is a type of linear polarizer. Moreover, the annealing property of 45°-TFGs was measured up to 700 ℃, in which the PER of grating started to decrease at 300℃ and reached to the minimum at 700℃. Based on these results, the 45°-TFGs can be used as ultra-wide bandwidth in-fiber polarizing devices.
Guo Xi,Xing Zhikun,Qin Huabao,Sun Qizhen,Liu Deming,Zhang Lin,Yan Zhijun. Study on polarization spectrum and annealing properties of 45°-tilted fiber gratings[J].Chinese Optics Letters,2019,17(5):05.