Spectroscopic properties of water free Nd2O3-doped low silica calcium aluminosilicate glasses

Instituto de Fı́sica de São Carlos, Grupo de Espectroscopia de Sólidos, Universidade de São Paulo, Av. Dr. Carlos Botelho 1465, 13560-250, São Carlos SP, Brazil; Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-970, Campinas SP, Brazil; Departamento de Física, Universidade Estadual de Maringá, Av. Colombo 5790, 87020-900, Maringá PR, Brazil
Journal of Non-Crystalline Solids (Impact Factor: 1.72). 01/2000; DOI: 10.1016/S0022-3093(00)00316-1

ABSTRACT In this work, low silica calcium aluminosilicate glasses (LSCA) doped with different concentrations of Nd2O3 were prepared under vacuum conditions and investigated through spectroscopic measurements. UV, visible and near IR optical absorption spectra, IR luminescence spectra, and fluorescent time decay were measured. Judd–Ofelt model was used in conjunction with these data to calculate intensity parameters and ), emission cross-section, radiative lifetime, branching ratio and fluorescence quantum efficiency. The up-conversion properties of Nd3+ were investigated following excitation, and both visible and UV up-conversion have been observed. These results combined with its high fluorescence quantum efficiency and excellent mechanical properties, suggest that this glass may be a candidate to be used as laser host material for near IR with a further possibility of application in the UV and visible spectral regions.

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