Absorption and emission cross sections of Er3+ in Al2O3 slab waveguides
Al2O3 slab waveguide films were doped with erbium using ion implantation to a peak concentration of 1.5 at. %. Prism coupling measurements show absorption caused by 4I15/2 → 4I13/2 intra-4f transitions in Er3+ with a maximum at 1.530 µm of 8 dB/cm. The Er3+ absorption cross section is determined as a function of wavelength. We used the McCumber theory to derive the emission cross section spectrum from the absorption results, which we then compared with the Er3+ photoluminescence spectrum. The peak absorption and emission cross sections are found to be 6 x 1021cm-2. The results are used to predict the optical gain performance of an Er-doped Al2O3 optical amplifier that operates around 1.5 µm.
van den Hoven, G.N, van der Elsken, J.A, Polman, A, van Dam, C, van Uffelen, J.W.M, & Smit, M.K. (1997). Absorption and emission cross sections of Er3+ in Al2O3 slab waveguides. Appl. Opt., 36, 3338–3341.