Fig. 1. Schematic of the synthesis process of C-dots@LTA composite material.

Fig. 2. (a) Experimental (upper) and simulated (lower) XRD patterns of LTA. (b) SEM image of as-synthesized LTA crystals. (c) Framework structure of the LTA single crystal retrieved from single crystal XRD data.

Fig. 3. (a) TEM image (inset: size distribution), (b) high-resolution TEM image, (c) powder XRD pattern, (d) Raman spectrum of as-synthesized C-dots.

Fig. 4. (a) Schematic diagram of the erbium-doped and ytterbium-doped fiber laser. (b) The setup of a balanced twin-detector measurement. The normalized absorption of the C-dots@LTA SA as a function of pump pulse peak intensity with excitation wavelength of (c) 1550 nm and (d) 1050 nm, respectively: dots, measured data; red line, fitting to the data.

Fig. 5. Output characteristic of the EDFL operated in mode-locking state. (a) Emission spectrum. (b) Pulse train. (c) Single pulse profile. (d) RF spectrum. (e) Output power as a function of the pump power. (f) The output spectrum measured every 6 h showing long-term stability of the mode-locking soliton state.

Fig. 6. Output characteristic of the YDFL operated in mode-locking state. (a) Emission spectrum. (b) Pulse train. (c) Single pulse profile. (d) RF spectrum. (e) Output power as a function of the pump power. (f) The output spectrum measured every 6 h showing long-term stability of the mode-locking dissipative soliton state.

Table 1. Typical Mode-Locked Fiber Lasers with Different Carbon-Based SAs