White Up-Conversion Luminescence in Rare-Earth-Ion-Doped YAlO3 Nanocrystals

Room-temperature bright white up-conversion (UC) luminescence in Yb 3+ /Er 3+ /Tm 3+ ion-doped YAlO 3 nanocrystals was achieved under diode laser excitation of 974.5 nm. The white light consists of the blue ( 1 G 4 → 3 H 6 of Tm 3+ ), green ( 2 H 11/2 / 4 S 3/2 → 4 I 15/2 of Er 3+ ), and red ( 1 G 4 → 3 F 4 of Tm 3+ and 4 F 9/2 → 4 I 15/2 of Er 3+ ) UC emissions. The UC mechanisms were proposed based on spectral, pump power dependence and kinetic analyses. The white light may be a possible candidate for applications in the field of lighting, displays, and photonics.