INFRARED TO VISIBLE UP-CONVERSION FLUORESCENCE SPECTROSCOPY IN ER3-DOPED CHALCOGENIDE GLASS()

Infrared to visible frequency up-conversion fluorescence spectroscopy in erbium-doped chalcogenide glass samples excited at 1.06 and 1.54 mu m, is experimentally investigated. For 1.06 mu m pumping, two-photon absorption and phonon-assisted energy transfer account for the excitat ion of the H-2(11/2), S-4(3/2) and F-4(9/2) emitting levels, yielding intense green emission at 530 and 555 nm and low intensity light at 67 0 nm, respectively. For excitation at 1.54 mu m, much higher up-conver sion efficiencies were obtained with the red emission signal around 67 0 nm presenting higher intensity than the green fluorescence signals. At this excitation wavelength the population of the H-2(11/2), S-4(3/2 ) and F-4(9/2) excited-state emitting levels is accomplished via energ y-transfer and phonon-assisted decays. Saturation of the up-conversion efficiency for 1.54 mu m pumping was also observed. (C) 1998 Elsevier Science B.V. All rights reserved.