Novel highly efficient in-band pump wavelengths for Ho-doped fiber amplifiers

We report the design and performance of Holmium-doped fiber amplifiers (HDFAs) with novel alternative in-band pump wavelengths in the 1720-2000 nm spectral region. We demonstrate through simulations that pump wavelengths of 1840-1860 nm can yield significantly improved output power (3-6dB), gain (8-10 dB) , and optical-optical conversion efficiency compared to the previous technical and industry standard pump wavelength of 1940 nm. Experimental results fully confirm our simulations.