Fig. 1. Relationship among ambient refractive index, diameter of tapered micro/nano fiber, and its interference sensitivity. (a) Structural diagram of tapered micro/nano fiber; (b) variation of effective refractive index difference under different wavelength and environmental refractive index; (c) sensitivity at different wavelengths for ambient refractive index of 1.333; (d) interference curves of tapered micro/nano fibers with different waist diameters

Fig. 2. Interference spectrum changes during scanning. (a) Variation curve of effective refractive index difference for different radius; (b) schematic diagram of droplet scanning experimental device of tapered micro/nano fiber; (c) change of relative light intensity for 50 spectral scans; (d) interference spectra in scanning process

Fig. 3. Structure and mode changes of tapered micro nano/fiber during processing. (a) Schematic diagram of experimental device; (b) taper diameter of tapered micro/nano fiber; (c) light intensity transmittance and spectrum during tapered micro/nano fiber processing

Fig. 4. Interference spectra and interference peak sensitivity calculation curves of sensing process. (a) Interference spectra of tapered micro/nano fiber; (b) fitting curves of wavelength-refractive index