Supercontinuum generation up to 2.7 µm in the germanate-glass-core and silica-glass-cladding fiber

We have realized supercontinuum source based on the silica-cladding fiber with the germanate-glass-core pumped by Q-switched Er-doped fiber laser. The long-wavelength edge of the spectrum obtained is located at 2.7 μm. To our best knowledge it is the longest wavelength for the silica based fiber. Average output power as high as 0.49 W was measured. Intensity variation in the range of 1.6 – 2.7 μm was much less than one decade. The fibers with different lengths were tested.