Dependence of Luminescence of NaYF₄:Yb/Tm Complexes on Mode and Intensity of Optical Pumping at Different Concentrations of Activators and Sensitisers

In this study, the influence of the concentrations of ytterbium and thulium ions on the dependence of the luminescence intensity of NaYF ₄ :Yb/Tm nanoparticles on the mode and intensity of optical pumping is considered. Two modes of luminescence excitation are analyzed: continuous and pulsed. It has been established that variation in the concentrations of ytterbium and thulium does not lead to a change in the shape of the curve describing the dependence of the luminescence intensity of the nanoparticles on the intensity of optical pumping under both pulsed and continuous excitation.