Energy transfer and energy level decay processes in Tm³⁺-doped tellurite glass

Autor(es)

Gomes, Laercio ; Lousteau, Joris ; Milanese, Daniel ; Scarpignato, Gerardo C. ; Jackson, Stuart D.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Physics; v. 111, n. 6, p. 8-pg., 2012-03-15.

Resumo

The primary excited state decay and energy transfer processes in singly Tm3+-doped TeO2:ZnO:Bi2O3:GeO2 (TZBG) glass relating to the F-3(4) -> H-3(6) similar to 1.85 mu m laser transition have been investigated in detail using time-resolved fluorescence spectroscopy. Selective laser excitation of the H-3(4) manifold at 794 nm, the H-3(5) manifold at 1220 nm, and F-3(4) manifold at 1760 nm has established that the H-3(5) manifold is entirely quenched by multiphonon relaxation in tellurite glass. The luminescence from the H-3(4) manifold with an emission peak at 1465 nm suffers strong suppression due to cross relaxation that populates the F-3(4) level with a near quadratic dependence on the Tm3+ concentration. The F-3(4) lifetime becomes longer as the Tm3+ concentration increases due to energy migration and decreases to 2.92 ms when [Tm3+] = 4 mol. % as a result of quasi-resonant energy transfer to free OH- radicals present in the glass at concentrations between 1 x 10(18) cm(-3) and 2 x 10(18) cm(-3). Judd-Ofelt theory in conjunction with absorption measurements were used to obtain the radiative lifetimes and branching ratios of the energy levels located below 25 000 cm(-1). The spectroscopic parameters, the cross relaxation and Tm3+(F-3(4)) -> OH- energy transfer rates were used in a numerical model for laser transitions emitting at 2335 nm and 1865 nm. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3694747] (AU)

• Processo FAPESP: 00/10986-0 - Estudo de geração de radiação ultravioleta pela excitação multifotônica de íons de Nd(3+) e Er(3+) em cristais fluoretos
• Beneficiário: Laercio Gomes
• Modalidade de apoio: Auxílio à Pesquisa - Regular