Fig. 1. Reflection spectra of Brillouin scattering. (a) Effect of refractive index modulation coefficient on reflection spectra; (b) effect of grating length on reflection spectra

Fig. 2. Experimental setup for Brillouin scattering

Fig. 3. Spectra of experimental measurement. (a) Spontaneous Brillouin scattering; (b) SBS

Fig. 4. Structure of transmission matrix

Fig. 5. Reflection spectrum distributions of SBS. (a) Reflection spectra of non-uniform refractive index period grating with different refractive index modulation coefficients; (b) reflection spectra of non-uniform refractive index period grating with different periodic modulation coefficients

Fig. 6. Comparison of theoretical and experimental results of SBS reflectance spectra of non-uniform refractive index modulated grating. (a) C_x=1.6×10^-3, T=20 ℃; (b) C_x=1.7×10^-3, T=30 ℃; (c) C_x=1.8×10^-3, T=40 ℃

Fig. 7. Frequency shift varies with refractive index. (a) Fitted curve of experimental measurement results; (b) theoretical simulation result (illustration in upper right shows change of refractive index with temperature)

Fig. 8. Linewidth varies with refractive index. (a) Fitted curve of experimental measurement results; (b) theoretical simulation results (illustration in upper left shows change of refractive index with temperature)

Fig. 9. Energy reflectivity varies with refractive index. (a) Fitted curve of experimental measurement results; (b) theoretical simulation results (illustration shows change of refractive index with temperature)