Filter Properties of Chirped Fiber Bragg Grating Fabry-Perot Cavity: A Potential Wavelength Stabilizer of Diode Laser

We investigate filter properties of chirped fiber Bragg grating (CFBG) (Fabry-Perot) F-P cavity through analyzing the coupled wave equation from one-dimensional Helmholtz equation. We derive an approximate formula of the reflectivity of a CFBG F-P cavity, simulate the central wavelength detuning, and calculate the central wavelength shift with the increase of ambient temperature. In the experiments, we measured the spectra of a diode laser with an FBG/CFBG F-P cavity at 0°C-110°C. The experimental results show that the CFBG F-P cavity can help a diode laser to obtain a less central wavelength shift and a narrower 3 dB reflection bandwidth, compared with the FBG F-P cavity at 0°C-110°C. The research results indicate that the CFBG F-P cavity is a potential wavelength stabilizer of uncooled diode laser.