Ultra low thermal coefficient broadband super-fluorescent fiber source with radiation insensitivity characteristic

Abstract

In this paper, an Erbium-doped fiber-based, broadband super-fluorescent fiber source (SFS) is proposed and demonstrated. Using a broadband fiber Bragg grating (BFBG) with temperature compensated by attaching it upon a carbon fiber composite, it has a very low mean wavelength drift of 1.26 ppm/°C in temperature range 0 °C to 60 °C. The fluorescent fiber source structure is designed in a double-pass backward pumping structure to increase the amplified spontaneous emission (ASE) power. The output power variation in the whole ambient temperature range is only 0.42 dB and the average 3 dB bandwidth is 17.05 nm. In Gamma radiation experiment using 60CO y ray, the broadband super-fluorescent source may have the photo-annealing effect to reduce the radiation induced attenuation (RIA) effect. The output power is 9.63 dBm with 3 dB bandwidth of 16.8 nm for the super-fluorescent fiber source from 0 to 30 Krad of 60CO y ray radiation. The overall bandwidth variation is only 0.7%. The SFS structure we proposed is wavelength and power stable with characteristic of radiation insensitive. It is promising to be used as light source for fiber optic gyroscope.