Down-conversion process in Tb3+-Yb3+ co-doped Calibo glasses

The down-conversion process in Tb3+-Yb3+ co-doped Calibo glasses was studied. The emission, excitation and time-resolved measurements indicated the existence of an energy conversion through the excitation of Tb3+ ions to near-infrared emission by Yb3+ ions. The emission intensity dependence on excitation power confirms that the one-photon process is responsible for the Yb3+ emission. An enhanced Yb3+ emission was observed with Yb3+ doping and an optimal energy transfer efficiency of 32% was obtained before reaching near-infrared emission quenching. The mechanism of the non-resonant energy transfer from Tb3+ to Yb3+ is discussed in terms of the Tb3+-Yb3+ cross-relaxation and multiphonon decay processes. (C) 2012 Elsevier B.V. All rights reserved.

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

Instituto Nacional de Nanotecnologia para Marcadores Integrados (INAMI)

Instituto Nacional de Nanotecnologia para Marcadores Integrados (INAMI)