Sol–gel synthesis and photoluminescence of SiO₂–Si:Er³⁺ nanocomposite films

In this work, we report on sol–gel synthesis and photoluminescence of SiO₂–Si:Er³⁺ nanocomoposite films. The films were characterized by x-ray diffraction, field emission scanning electron microscope and photoluminescence measurements. We demonstrate that the incorporation of Si nanocrystals with sizes of 10–20 nm into the silica matrix resulted in strong Er-related PL in the infrared region peaking at 1535 nm and that the film can be well excited by non-resonant wavelengths (250–260 nm). The role of Si nanocrystals as sensitizers and the dependence of the Er-related PL on Er-doping concentration and annealing temperature are also discussed. (paper)