Fig. 1. Experimental setup of the dual-wavelength pumped Er:ZBLAN fiber laser. F1, CaF2 lens with f=18  mm; F2, ZnSe aspheric lens with f=12.7  mm; ESA, excited state absorption. Inset: the energy level diagram of Er:ZBLAN.

Fig. 2. (Color online) Residual pump power of 1973 nm as a function of 970 nm launched pump power for different launched powers at 1973 nm.

Fig. 3. (Color online) Output power as a function of the launched pump power at 1973 nm for different 970 nm pump powers of 1.16, 1.29, and 1.76 W, respectively.

Fig. 4. (Color online) Laser spectrum evolution with output power.

Fig. 5. Measurement of laser beam quality. Inset: beam profile.

Fig. 6. Power stability of the Er:ZBLAN fiber laser.