Excited-state absorption and up-conversion losses in the Nd-doped glasses for high-power lasers

Excited-state absorption spectra of two Nd-doped glasses, a silicate LSG91H and a phosphate LHG8 from Hoya, are reported. An adequate model based on u p-conversion energy transfers is then used to account for the shortening of the infrared fluorescence decays and the losses on the stored energies obs erved or predicted in this type of materials at high pump fluences.