Fig. 1. Schematic of preparation process. (a) Cavity Ⅰ；(b) cavity Ⅱ

Fig. 2. Optical image and interferometric spectrum of proposed fiber sensing probe. (a) Optical image; (b) interferometric spectrum

Fig. 3. Temperature response of fiber sensing probe. (a) Interference spectra at different temperatures; (b) linear fitting results of two interference peaks

Fig. 4. Setup for magnetic field detection

Fig. 5. Response of fiber sensing probe to magnetic field. (a) Interference spectra; (b) linear fitting results of two interference peaks