Upconversion luminescence, solids

Kadono K, Higuchi H, Takabashi M, Kawamoto Y, Tanaka H. Upconversion luminescence of Ga2S3-based sulfide glasses containing Er ions. J Non-Cryst Solids 1995 184 309. 

Liu J, Liu X, Kong X, Zhang H (2012) Controlled synthesis, formation mechanism and upconversion luminescence of NaYF4 Yb, Er nano-/submicrocrystals via ionothermal approach. J Solid State Chem 190 98-103... 

The d electron configuration is frequently stabilized by a metal-metal interaction in polynuclear complexes. The luminescence of such clusters will be discussed below. However, d ions in solid matrices are known to emit. For example, octahedral [Os Cl6] " in various host lattices shows an LF emission. A NIR VIS upconversion was achieved with Os in CsjZrClg [29]. 

Optical properties of Y2O3 ceramics, doped with rare-earth ions, are of special interest for some applications, such as solid-state lasers and scintillators [95]. Luminescence properties, such as upconversions, are also of special significance. For instance, REA"b co-doped Y2O3 transparent ceramics (RE = Er, Ho, Pr and Tm), exhibited very efficient NIR-visible upconverters [96]. 

Hoppe HA, Lutz H, Mrays P, Schnick W, Seilmeier A (2000) Luminescence in Eu -doped Ba2Si5Ng fluorescence, thermoluminescence, and upconversion. J Phys Chem Solids 61 2001... 

Solid-state lanthanide luminescent materials have the combined advantages of typical lanthanide luminescence and photophysical stability. In these materials, lanthanide ions are trapped into the rigid crystal host lattice, avoiding adverse quenching by environmental oscillators. Two types of luminescence modes, downconversion and upconversion, are known for lanthanide luminescence. Upconversion relates to a nonlinear optical process where two or more near-infrared (NIR) photons are absorbed sequentially to several real intermediate energy states and luminescence is emitted with a... 

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