Long lasting phosphorescence properties and multi-peak fitting on thermoluminescence of red LaAlO3:Eu3+ phosphor

Red long lasting phosphorescence(LLP) was firstly observed in LaAlO3:Eu3+ phosphor synthesized by solid state method at 1773 K. It reveals that the Eu3+ ions occupy the asymmetric La3+ sites, resulting in the orange-red emission of Eu3+. The LLP of the optimum LaAlO3:0.6%Eu3+ sample can come to about 2000 s according to a definition of 0.32 mcd/m2. The LLP decay curve can not be fitted even by a function of three exponential terms, due to the complicated retrapping process of carriers. The result of a classical multi-peak fitting method on thermoluminescence reveals that the excellent LLP performance of LaAlO3:Eu3+ material originates from the rich distribution of shallow traps(E=0.7875 eV).