Enhanced spatial energy transfer in Er-doped silica glasses

Energy transfer processes and the related photon diffusion have been investigated in Er-doped silica glasses. The spatial distribution of the luminescence on the sample surface was scanned by the spatially-resolved microluminescence technique for several samples with different Er 3+-ion concentrations. Efficient long-range photon diffusion for the 1.54 μm emission was found at 1.85 wt.%. We propose an energy transfer process between erbium ions randomly distributed throughout the glass medium. Each ion acts as absorbers and emitters in such a way that the energy is spatially transferred.