Fig. 1. All-fiber Er∶ZBLAN MIR laser at 2.8 µm based on dielectric film technology. (a) Laser setup; (b) designed structure of M1 film layer; (c) transmission spectrum of M1; (d) picture of AlF₃ endcap splicing

Fig. 2. Output performance of 10 W-level 2.8 µm all-fiber Er∶ZBLAN MIR laser. (a) 10.09 W output in real situation; (b) output spectrum; (c) laser power curve; (d) operational stability