White up-conversion luminescence in rare-earth-lon-doped YAlO3 nanocrystals

Room-temperature bright white up-conversion (UC) luminescence in Yb3+/Er3+/Tm3+ ion-doped YAlO3 nanocrystals was achieved under diode laser excitation of 974.5 nm. The white light consists of the blue ((1)G(4) -> H-3(6) of Tm3+), green (H-2(11/2)/ S-4(3/2) -> I-4(15/2) of Er3+), and red ((1)G(4) -> F-3(4) of Tm3+ and I-4(15/2) -> I-4(15/2) of Er3+) 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.