Spectral characterization of LiYbF4 upconverting nanoparticles

In this work, rare-earth-based nanoparticles based on LiYbF4 and doped with Er3+, Tm3+ and Ho3+ were investigated. The effect of the concentration of the dopant ions was thoroughly studied from a spectroscopic standpoint under 980 nm excitation. The upconversion emission that originates from the absorption of the optical energy from the Yb3+ ions in the crystal lattice and the subsequent energy transfer to the other rare earth in the lattice (i.e., Er3+, Tm3+ or Ho3+) highly depends on the concentration of the latter ion. Overall, the findings in this manuscripts provide important insights into the properties and rational design of upconverting nanoparticles.