Up-conversion studied by selective time resolved excitation techniques in Pr3+ : LaF3

Abstract

A strong blue fluorescence has been observed following orange-yellow laser excitation in the 1D2 multiplet of Pr3+ : LaF3. This blue fluorescence has different time evolution depending on the excitation wavelength within the absorption line. Time resolved excitation techniques have been used to study this time evolution. It is shown that satellite lines, which accompany the main line, are due to ions between which energy transfer is very active. A mechanism is proposed for the observed up-conversion which is in good agreement both with our results and with observations reported by others. The nature of the interaction between the ions of the satellite lines and that of the interaction responsible for the energy transfer are discussed

Up-conversion fluorescence of Pr3+ ions in PbWO4 single crystal

“…There are no levels lying at approximately twice the excitation energy above the ground state [4]. Similar behavior has been found in the other materials [8,9], which was attributed to a redistribution of energy between two ions pairs. It is known that two 1 D 2 ions which couple between themselves can also undergo an up-conversion process according to 1 [10].…”

Frequency upconversion involving triads and quartets of ions in a Pr3+/Nd3+ codoped fluoroindate glass

“…For instance, in crystals doped with Pr 3ϩ , a process was identified by which two Pr 3ϩ ions in the excited state 1 D 2 exchange energy in such way that one of the ions decays nonradiatively to the ground state while the other is promoted to state 3 P 0 , and from there, blue emission is observed due to decay to the ground state. [5][6][7] In glasses, this effect was reported, for example, in…”

Investigation of static electric dipole–dipole coupling induced optical inhomogeneous broadening in Eu3+:Y2SiO5

“…Given the proximity of the two ions in a pair site, their inhomogeneous broadening will not be totally random to as they will experience similar inhomogeneous fields and hence some degree of correlation in their optical frequencies. Evidence for such correlations have been observed in rareearth-doped crystals during upconversion studies [8]. The simulation described in Section 2 along with the value of b determined above, can be used to estimate the distribution of the frequency difference between the ions in a given pair site.…”