Spectral luminescence properties of nanostructured Ce-Nd-Containing silica gel-glasses

Complex Ce$^{4+}$-Nd$^{3+}$ centers were formed in silica gel-glasses. These centers were characterized by weak cross-relaxation quenching of luminescence; an increased luminescence branching ratio in the $^4F_{3/2}\to ^4I_{11/2}, ^4I_{13/2}$ transitions; strong structuring of the analogous spectral bands; and effective intracenter sensitization of luminescence. On reducing the Ce$^{4+}$ ions to the triply charged state, the structure of the luminescence bands of Nd$^{3+}$ ions became weaker and the ratio of their intensities approached the value typical of an Nd-containing silica gel-glass.