Strong cooperative upconversion luminescence of ytterbium doped oxyfluoride nanophase vitroceramics

Improving pure red upconversion emission of Co-doped Y2O3:Yb3+–Er3+ nanocrystals with a combination of sodium sulfide and surfactant Pluronic-F127

“…The number of photons involved in the upconversion process was investigated by analyzing the dependence of the upconverted signal intensity (I upc ) as function of the pumping intensity (I pump ). It is well-known that this dependence is expressed by the equation I upc ¼kI n pump where n denotes the number of photons absorbed to produce such upconverted emission [50,51]. Fig.…”

Luminescence behavior of Yb3+heavy-doped yttrium lanthanum oxide transparent ceramics

“…The broad absorption bands of (Yb x Y 0.90 − x La 0.1 ) 2 O 3 (x = 0.05-0.15) ceramics in 900-1000 nm make it suitable to be coupled by LD, hence the temperature control of LD is unnecessary [6]. By assuming a Gaussian-shaped emission band, emission cross-section (σ em ) of Yb 3+ ion is estimated from Füchtbauer-Ladenburg (F-L) formula [7,8]: Cooperative up-conversion is a well-studied phenomenon since firstly observed inYbPO 4 by Nakazawa and Shionoyain [12] and numerous cooperative up-conversion researches such as Yb 3+ -Er 3+ ions or Yb 3+ -Yb 3+ ions have been carried out [13,14]. Meanwhile up-conversion luminescence has many interesting applications, including data-storage, 3-d volumetric display, guard-against-forge applications, sensor, laser imaging and so on.…”

The nano-crystallization and fluorescence of terbium doped Na2O/K2O/CaO/CaF2/Al2O3/SiO2 glasses

“…In the past few years, much attention has been paid to Tb 3+ doped glasses due to their optical properties which are advantageous for numerous applications. [1][2][3][4] If the chemical composition of oxyuoride glass-ceramics is carefully tailored, thermal treatment at temperatures slightly above the glass transition temperature T g , results in the precipitation of uorides. Here, the formation of rare earth or alkaline earth uorides such as LaF 3 , NaGd(La)F 4 , CaF 2 , SrF 2 and BaF 2 have been described in the literature.…”