Fluorescence decay route of optical transition calculation for trivalent rare earth ions and its application for Er³⁺-doped NaYF₄ phosphor

Abstract

Usually, the optical transition properties of trivalent rare earth (RE) ions in transparent hosts can be quantitatively investigated in the framework of Judd-Ofelt theory. A standard and commonly accepted calculation...

An up-conversion luminophore with high quantum yield and brightness based on BaF2:Yb3+,Er3+ single crystals

“…Altogether, the obtained values of the radiative decay times are close to the results of other studies devoted to optical properties of Er 3+ ions in fluoride single crystals and micropowders. 76,[82][83][84] Whereas an acceptable level of conformity between theoretical prediction ( in Table S9) and experimental results ( in Table S6) for the 4 F 9/2 ⟶ 4 I 15/2 transition exists (the relative difference doesn´t exceed 20 % in most ( -)/ cases), for the case of 4 S 3/2 ⟶ 4 I 15/2 and 4 I 13/2 ⟶ 4 I 15/2 transitions a discrepancy between quantum yields extracted from the Judd-Ofelt calculation and the experimental one is significant. The values of estimated via Judd-Ofelt analysis always exceed unity for the 4 I 13/2 ⟶ 4 I 15/2 transition, because measured decay times () are longer than predicted radiative lifetimes ( r ).…”

Optical transition properties, internal quantum efficiencies, and temperature sensing of Er3+ doped BaGd2O4 phosphor with low maximum phonon energy

“…32 is carried out. The relative electric dipole transition rate for 4 I 13/2 → 4 I 15/2 can be calculated from below formula: 33 $$\begin{eqnarray}A{\rm{^{\prime}}}_{4{\rm{I}}13/2 \to 4{\rm{I}}15/2}^{{\rm{ED}}} = \frac{{64{\pi ^4}{e^2}{v^3}n{{\left( {{n^2} + 2} \right)}^2}}}{{27h\left( {2J + 1} \right)}}{\rm{\;}}\nonumber\\ \quad \mathop \sum \limits_{\lambda {\rm{\;}} = {\rm{\;}}2,{\rm{\;}}4,{\rm{\;}}6}\Omega {_\lambda ^{\rm{^{\prime}}}}{\left| {\langle \left( {S,L} \right) J\left| {{U^\lambda }} \right|\left( {S^{\prime},L{\rm{^{\prime}}},} \right)J{\rm{^{\prime}}}\rangle } \right|^2}\end{eqnarray}$$…”

“…The absolute magnetic dipole transition rate for 4 I 13/2 → 4 I 15/2 can be directly calculated from following equation: 33 $$\begin{eqnarray} && A_{4{\rm{I}}13/2 \to 4{\rm{I}}15/2}^{{\rm{MD}}} = \frac{{16{\pi ^4}{e^2}{n^3}}}{{3h\left( {2J + 1} \right){m^2}{c^2}}}{\rm{\;}} \nonumber \\ && \quad {\left| {\langle \left( {S,L} \right)J\left| {L + 2S} \right|\left( {S^{\prime},L{\rm{^{\prime}}},} \right)J{\rm{^{\prime}}}\rangle } \right|^2} \end{eqnarray}$$…”

“…In addition, Zhang et al 32 have developed an approach for calculating the Judd-Ofelt parameters of rare earth ion doped opaque materials, which is applicable for all the powdered samples as long as the diffuse-reflection spectrum for the studied material can be measured. Furthermore, Luo et al 33 have established a fluorescence decay route in which the Judd-Ofelt calculation procedure breaks the restriction on the shape and morphology of the studied samples.…”

Dual-Feedbacked Temperature Sensing of Er3+ in Fusiform-Polycrystalline-Implanted BaYF5/PAN Electrospun Fibers

“…Er 3+ ions with abundant ladder-like arranged energy levels are selected as the activator, which can be sensitized by Yb 3+ ions with a larger absorption cross section to generate dual- or multiphoton upconversion photoluminescence and attain large optical temperature sensitivity. − Furthermore, lanthanide fluoride has low phonon energy, high upconversion (UC) efficiency, and rapid thermal reaction such that it can sense/experience a slight change in the temperature of the sample. Here, in order to get high-quality FIR-based temperature sensing, BaYF 5 powder has been employed as an optical media whose UC power conversion efficiencies are rivaling GaP light-emitting diodes. − In addition, at the same time, the adopted electrospinning technology has solved the limitation of powder materials caused by their structure and morphology when applied in complex microregions. − Functional fibers can combine the integrity and temperature-sensing properties of powder and the flexibility and processability of the polymer, which provide a probability of optical temperature sensing in microareas.…”