Modelling and simulation of the luminescence of rare earth (RE) ions and niobium activated yttrium tantalate host lattices

The blue light emission from yttrium niobiumtantalate Y(Ta, Nb)O4 phosphors under X-ray excitation, is associated with TaO4³⁻ and NbO4³⁻ groups from the host crystalline lattice. Such luminescent emission could be shifted toward longer wavelengths when activators: rare earth ions such Eu³⁺ or Tb³⁺ replace partially the yttrium ions in the host crystalline lattice. The paper presents the analogical modelling and numerical simulation for fitting the equation to experimental data by a regression analysis. The program determines the theoretical parameters for incorporation degree of activators: KAc and Emax and they are compared with the values of the same parameters experimentally determined.