Fig. 1. Absorption spectra and surface photos of ZBLAN glass after dipping in water for different time^[28]. (a) Absorption spectra of ZBLAN glass after dipping in water for 0, 5, 30, 60, and 90 min, respectively; (b) photos of ZBLAN glass surface dipping in water for 0.5, 2, 4, 6, and 7 d, respectively

Fig. 2. Transmission spectra of TBY and ABCYSMT glasses before and after dipping in water^[37]

Fig. 3. Loss spectra of silica, AlF₃ and ZBLAN glass fiber

Fig. 4. Measured SC spectrm from 2-cm-long fluoride fiber end when average pump power of 1450 nm femtosecond laser is fixed at 20 mW^[36]

Fig. 5. Schematic of high-power mid-IR SC system^[24]

Fig. 6. Output SC spectra with average output powers of 8.2, 15.5, and 21.8 W^[24]

Fig. 7. Spectral comparison at different positions in the system^[27]

Fig. 8. Core diameter variance in tapered fluorotellurite microstructured fiber and GVD curves of fiber segments with different core diameters^[33]. (a) Core diameter versus position in the fiber, inset: scanning electron micrograph of untapered fiber; (b) calculated GVD curves of fiber segments with core diameters of 1.1, 3, and 6 μm, respectively

Fig. 9. Schematic of experimental setup for SC generation^[33]

Fig. 10. Output SC spectra from fluorotellurite microstructured fiber (MF) for different pump powers^[33]. (a) Tapered fluorotellurite fiber; (b) untapered fluorotellurite fiber

Fig. 11. Core diameters of tapered fluorotellurite glass fiber and GVD curves of fiber segments with different core diameters. (a) Core diameter of tapered fluorotellurite fiber versus position in the fiber, inset: scanning electron micrograph of untapered fluorotellurite fiber; (b) calculated GVD curves of fluorotellurite fibers with different core diameters

Fig. 12. Schematic of experimental setup and parameters of pump laser. (a) Experimental setup for SC generation; (b) output spectrum of 2 μm femtosecond laser; (c) single pulse profile of pump laser

Fig. 13. Output SC spectra and relative powers from tapered fluorotellurite fiber for different pump powers. (a) Measured SC spectra from tapered fiber for different average pump powers of 0.26, 0.42, 0.6, 0.79, 0.99, 1.2, 1.38 and 1.57 W from bottom to top, respectively; (b) average output power of SC laser source versus pump power

Fig. 14. Parameters of pump laser and schematic of experimental setup. (a) Output spectrum of 2 μm femtosecond laser amplifying system when average output power is 40 W; (b) output power of 2 μm femtosecond laser amplifying system versus pump power of 793 nm pump laser; (c) experimental setup for high-power SC laser generation

Fig. 15. Calculated dispersion curve of all-solid high-NA fluorotellurite fiber with core diameter of 11 μm, inset: scanning electron micrograph of fiber end

Fig. 16. Output SC spectra and relative powers from tapered fluorotellurite fiber for different pump powers. (a) Measured SC spectra from all solid high-NA fluorotellurite fiber for different average pump powers of 1980 nm fiber laser; (b) output power of obtained SC light source versus pump power