Stable 35-W Er: ZBLAN fiber laser with CaF 2 end caps

This is the authors' abstract. We don't add key points for this paper.

We successfully demonstrate a 2838 nm erbium-doped fluoride fiber laser with an average output power of 35 W, and record an hour of continuous operation at 30 W. The temporal and spectral stability of the 2.8 μ m laser represent a significant improvement over previous work. The success of this work can be largely attributed to the development of component technologies such as fiber Bragg grating fabrication and fine fusion splicing of fiber/fiber and a fiber endcap.