Judd–Ofelt analysis of the Er3+ (4f11) absorption intensities in Er3+−doped garnets

Abstract

Spectroscopic and laser properties of three different Er3+−doped garnet systems are characterized by employing the Judd–Ofelt (JO) analysis. The three garnet hosts are Y3Al5O12 (YAG), Y3Sc2Ga3O12 (YSGG), and Gd3Ga5O12 (GGG). The JO model has been applied to the room temperature absorption intensities of Er3+ (4f11) transitions to establish the so-called JO intensity parameters: Ω2, Ω4, and Ω6 in the three garnet hosts. The intensity parameters are used to determine the radiative decay rates (emission probabilities of transitions) and branching ratios of the Er3+ transitions from the excited state J manifolds to the lower-lying J′ manifolds. The predicted decay rates and branching ratios of these Er3+ transitions in YAG, YSGG, and GGG hosts are compared. From the radiative decay rates, the radiative lifetimes of the Er3+ excited states are determined in the three garnets and are also compared. We also report the spectroscopic quality factors, Ω4/Ω6, obtained for the three garnets. The quantum efficiencies of the I413/2→I415/2 Er3+ transition in YAG, YSGG, and GGG are determined to be ∼79%, 82%, and 85%, respectively.

Synthesis, structural investigation and luminescence spectroscopy of nanocrystalline Gd3Ga5O12 doped with lanthanide ions

“…The radiative lifetime of the emitting states, estimated from a Judd-Ofelt analysis for a Er 3+ -doped GGG single crystal, is 200-220 s [19]. Therefore, the quantum efficiency of the emission in the green region at 550 nm for the Er 3+ -doped CP nanocrystalline sample turns out to be about 45%.…”

Spectroscopic properties and thermal stability of Er3+-doped germanate–borate glasses

“…2 it can be seen that the optical energy gaps of these glasses increased from 4.1 to 5.5 eV with increasing borate content, which indicated that introducing borate into germanate glass has extended the transparency of the glass toward UV region and make it possible for rare earth ions to be pumped in UV region. According to Judd-Ofelt theory the phenomenological JuddOfelt parameters of rare earths in various matrices can be predicted by these measured absorption spectra and the refractive index of the host material [29]. It is generally accepted that˝2 is related with the symmetry of the glass hosts and the covalency of the rare earth-ligand bond.˝6 is inversely proportional to the covalency of the rare earth-ligand bond [30,31].…”

Spectroscopic properties of Pr3+:Gd3Ga5O12 crystal

“…where N 0 is the Pr 3+ concentration in the crystal (unit: ion/cm 3 ), is the mean wavelength of the absorption band, c is the vacuum speed of light, e is the electron charge, h is Planck's constant, J is the total angular momentum of the ground state (J = 4 in Pr 3+ ), n is the refractive index which can be calculated from the Sellmeier dispersion equation [31]:…”