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Study on temperature and stress characteristics of double-clad fiber Bragg gratings

The temperature and stress characteristics of double-clad fiber Bragg grating are investigated, respectively. The thermal decay characteristics according to the different anneal thermal, 100°C, 150°C, 200°C and 250°C are got. These results are very significant to estimate the properties of grating, such as thermal, wavelength and anneal time. Birefringence effect of the grating is also detected in rectangular inner cladding DCF gratings. By applying stress on the grating, strain is induced. One reflection peak of double-clad fiber Bragg grating becomes two peaks. The relation between the stress and the peak shift is obtained. The two reflection peaks can be tuned from 0 to 0.8nm. These results are more significant for estimate the sensor properties of the DCF Bragg gratings.