Excited-state absorption spectroscopy of Er3+-doped Y3Al5O12, YVO4, and phosphate glass

The spectra of excited-state absorption (ESA) and stimulated-emission (SE) cross sections of Er3+ in Y3Al5O12 YVO4, and phosphate glass have been registered between 0.4 and 3 mu m with a pump and probe technique. The experimental setup, based on the use of cw light sources, is described in detail. The incidence of ESA on the laser properties of these Er3+ -doped oxide hosts is evaluated particularly around 0.55, 1.6, and 2.8 mu m, corresponding to the S-4(3/2) --> I-4(15/2), I-4(13/2) --> I-4(15/2), and I-4(11/2) --> I-4(13/2) laser transitions, respectively. The migration [(I-4(13/2), I-4(15/2)) --> (I-4(15/2), I-4(13/2))] and up-conversion [(I-4(13/2), I-4(13/2)) --> (I-4(9/2), I-4(15/2))] energy transfers involved in some laser operations are analyzed by deducing the energy-transfer microparameters C-DD and C-DA from ESA and SE measurements. The Judd-Ofelt analysis, usually applied from the ground-state manifold, is then used to evaluate the ESA integrated cross sections and these calculated cross sections are found equal to the measured ones within about 20%. [S0163-1829(99)08539-2].