Correlation between rare-earth oscillator strengths and rare-earth–valence-band interactions in neodymium-dopedYMO4(M=

Crystal Growth and Structure of the New Ferrimagnetic Oxyphosphate PbFe3O(PO4)3

“…10 -5 -10 -6 ) of crystals of Nd-doped YPO 4 have been found to result from covalent interactions between the rare-earth 4f and 5d states and the mainly O 2p state valence band top levels. [1] The intense Eu 3+ 5 D 0 Ǟ 7 F 0 emission in Ca 10-x Eu x (PO 4 ) 6 O 1+x/2 has been interpreted in terms of J-JЈ mixing, which arises from both an unexpectedly high B 0 2 crystal field parameter (ca. -2000 cm -1 ) and a low-lying 7 F 1 energy level (deduced from low-temperature magnetic susceptibility measurements).…”

Absorptions UV dans le fonctionnement des sources lasers solides à ions de terres rares

“…R X et R Y sont les rayons ioniques [19] des ions X 3+ et Y 3+ (l'ion auquel se substitue l'ion dopant X 3+ dans LiYF 4 ) et R mesure la variation d'énergie de liaison par unité de variation de rayon ionique. On détermine ainsi la position du niveau fondamental de la configuration 4f n de tous les ions de terres rares trivalents à partir des quelques données disponibles dans la littérature [20][21][22] et en traitant E L et R comme des paramètres ajustables. Dans le cas de LiYF 4 , comme le montre la Figure 2, le meilleur ajustement des données expérimentales est obtenu pour E L = 29.87 eV et R = 13.98 eV/ug es positions des niveaux d'énergie les plus bas de la première configuration électronique excitée 4f n−1 5d sont déduits des spectres expérimentaux reportés dans les références [1][2][3]23].…”

Solvothermal synthesis and upconversion properties of about 10 nm orthorhombic LuF3: Yb3+, Er3+ rectangular nanocrystals

“…32 So far, however, many investigations have demonstrated that trivalent rare earth ions doped Lu-based compounds, such as Yb 3+ and Ln 3+ (Ln = Er 3+ , Ho 3+ , Tm 3+ ) codoped β-NaLuF 4 , Yb 3+ and Er 3+ codoped Lu 2 O 3 show stronger UC luminescence than that found for the corresponding Y-based compounds. 33,34 This may be due to Lu unique electronic state at the top of the valence, which results to the increase of the oscillator strength of the doped rare earth ions in the crystals, according to the intensity-borrowing mechanism proposed by Guillot-Noel et al 35 Therefore, LuF 3 , owning the similar structure to YF 3 , may be a more promising host for UC behavior than YF 3 .…”