Fig. 1. Extrinsic Fabry-Perot cavity optical fiber sensors

Fig. 2. Spectra of the fiber F-P probe sensor in air before and after covering GO

Fig. 3. Surface morphology of the F-P probe

Fig. 4. Energy spectrum of the probe surface

Fig. 5. Diagram of RI testing system

Fig. 6. Spectral correspondence and linear fitting for RI sensitivity

Fig. 7. Spectral correspondence and linear fitting for temperature sensitivity

Fig. 8. Stability test results