Upconversion and Anti-Stokes Processes With f and d Ions in Solids

GOTR, UMR 7574-CNRS, 1, Place A-Briand, 92195 Meudon Cedex, France.
Chemical Reviews (Impact Factor: 46.57). 02/2004; 104(1):139-73. DOI: 10.1021/cr020357g
Source: PubMed


The anti-Stokes emissions or upconversion processes, for which emissions was found to exceed excitation energies by 10-100 kT, were presented. The dissolution of nanoparticles (6-8 nm) of Yb-Er- and Yb-Tm doped LuPO 4 as colloids in chloroform solutions was demonstrated. The Nd 3+-Yb3+ codoped YA nanocrystalline cemramics were also studied. It was observed that in thermoluminescence, where traps were emptied by excitation energies of the order of kT, constituted a field of anti-Stokes emission of its own.

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    • "Due to the precipitation of fluoride nanocrystals, the local environment around rare-earth ions changes from oxides to fluorides with low effective phonon energy. This change decreases the non-radiative probabilities of certain energy levels of rare earth ions, and results in increased visible and infrared luminescence [6]. The changes in local environment of rare earth ions have been inferred from the changes in lifetimes of certain energy levels [7] [8]. "
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    Materials Characterization 10/2014; 98. DOI:10.1016/j.matchar.2014.10.020 · 1.85 Impact Factor
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    • "nm, indicating higher population of excited states [3]. The shift of the peaks between the reference and the CPC-45 ο UC-PV device however, is independent of the UC phosphor or the configuration and is an artefact caused during acquisition of the data. "
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    29th European Photovoltaic Solar Energy Conference and Exhibition, Amsterdam, the Netherlands; 09/2014
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