Fig. 1. MZI based on waist-enlarged fusion

Fig. 2. Experimental setup for glycerol solution measurement

Fig. 3. Spectrogram of MZI under different mass fractionsof glycerol solution

Fig. 4. Relationship between interference dip of characteristic wavelength and refractive index

Fig. 5. Structure of tunable self-seeded multiwavelength Brillouin laser

Fig. 6. Multiwavelength spectrogram without axial strain under the pump power of 200 mW

Fig. 7. Tunable range spectra of glycerol solution under different mass fractions