Downconversion and upconversion dynamics in Pr-doped Y3Al5O12 crystals

Abstract

We have investigated the spectroscopic properties of praseodymium ion in a Y3Al5O12 sample. We obtained the luminescence spectra by exciting selectively the sample at 460 and 599nm, resulting in the excitation of the P03 and D21 levels, respectively. With excitation in the P03 level we obtained emission from this level and from the D21 level. We used time resolved spectra and decay pattern inspection to assign spectral lines to specific radiative transitions. With excitation in the D21 level we observed luminescence emitted by the same level and upconverted emission from the P03 level and the (4f5d) band. The experimental data indicate that the mechanism responsible for the upconversion processes is excited state absorption. We found the upconverted emission from P03 and the (4f5d) band to be proportional to the square of the excitation energy and to the cube of the excitation energy, respectively.

The f–f Emission of Pr<SUP>3+</SUP> Ion as an Optical Probe for the Structural Properties of YAG Nanoceramics

“…The values obtained from this analysis are plotted in Figure 4( decay time of 1 D 2 , which is much more strongly affected by complicated quenching processes than 1 P 0 , is about one order of magnitude shorter than for the corresponding single crystal. 18 This suggests, that radiative and nonradiative relaxation processes, due to surface effects and structural distortions present in the nanoparticles, 19 are generally much stronger for nanosized grains compared to the single crystals doped with the same Pr 3+ content. As it can be seen in Figure 4( relatively stronger with increasing pressure, compared to 3 P 0 → 3 H 4 .…”

Spectroscopic properties of Pr3+:Gd3Ga5O12 crystal

“…And the lifetime the 1 D 2 manifold is estimated to be 118.4 s by using = (B 1 1 2 + B 2 2 2 )/(B 1 1 + B 2 2 ) [29], which is much longer than that of 3 P 0 level. The experimental lifetime value of the 1 D 2 level can be compared to that of 1 mol%Pr:GGG nanocrystalline: 110s [25], 0.5% Pr 3+ :YAG: 110s [45] and of 1% Pr 3+ :YAP: 28s [43]. It is interesting to point that at 4 K the decay 1 D 2 → 3 H 4 profile of Pr:GGG is exponential with a lifetime of 260 s [23], as in contrast with the above results of this job.…”

Up-conversion and fluorescence quenching processes studies in highly Pr3+-doped YAG waveguides

“…1. No emission from 4f5d was detected, although it was expected as reported in [5,9]. As previously, the dynamics of 1 D 2 and upconverted 3 P 0 emission was recorded.…”

“…Despite this, some processes taking place within Pr ions in YAG matrix are still unexplored or need clarification. This could explain the renewed interest in investigations of Pr:YAG optical properties [9,10]. Moreover, all the experimental data available up-to-now referred to relatively lightly doped, bulk materials.…”