Study of neodymium photoluminescence and energy transfer in silicon-based gels

This paper reports an investigation of the three $^4F_3/2$–$^4I_n/2$ emissions of Nd${3+} ions in the red and near infrared in silica gel films containing quantum dots of silicon, with comparison to those in pure silica. Measurements of excitation efficiency at various wavelengths and of PL yields as a function of the Nd concentration show that Nd is more soluble in the substoichiometric oxide obtained from triethoxysilane gels and that the energy of excitons in Si clusters is transferred to G levels of the lanthanide, with an effect of enhancement of the $^4F_3/2$–$^4I_n/2$ emissions.