Gouveia-Neto, A. S.da Costa, E. B.Bueno, L. A.Ribeiro, SJL2014-05-202014-05-202004-08-01Optical Materials. Amsterdam: Elsevier B.V., v. 26, n. 3, p. 271-274, 2004.0925-3467http://hdl.handle.net/11449/33687Blue, green, red, and near-infrared upconversion luminescence in the wavelength region of 480-740 nm in Pr3+/Yb3+-codoped lead-cadmium-germanate glass under 980 nm diode laser excitation, is presented. Upconversion emission peaks around 485, 530, 610, 645, and 725 nm which were ascribed to the P-3(0)-H-3(J) (J = 4, 5, and 6), and P-3(0)-F-3(J) (J = 2, 3, and 4), transitions, respectively, were observed. The population of the praseodymium upper P-3(0) emitting level was accomplished through a combination of ground-state absorption of Yb3+ ions at the F-2(7/2), energy-transfer Yb3+(2F(5/2))-Pr3+(H-3(4)), and excited-state absorption of Pr3+ ions provoking the (1)G(4)-P-3(0) transition. The dependence of the upconversion luminescence upon the Yb3+-concentration and diode laser power, is also examined, in order to subsidize the proposed upconversion excitation mechanism. (C) 2004 Elsevier B,V. All rights reserved.271-274engluminescencerare-earthglassthermal-effectupconversionArtigo10.1016/j.optmat.2003.12.012WOS:000223075000011Acesso restrito