Laser-Activated Luminescence of BaAl2O4:Eu

Copyright © 2020 The Author(s). In this article the laser-activated (LA) luminescence of BaAl2O4 doped with 3 mol% Eu2+ and SrAl2O4 doped with 700 ppm Eu2+ is described. The LA spectrum of BaAl2O4:Eu did not show any emission from Eu2+, but rather luminescence from the Eu3+ ion. This surprising result is explained in terms of ionization of the excited Eu2+ ions (photo-ionization), while the freed electrons are trapped in an excited state of the F-centre: this is considered to be a deep trap. The temperature of the ferroelectric-paraelectric phase transition in BaAl2O4 has been determined at ≈180 °C from the Raman spectra recorded at various temperatures.EPSRC and Technology Strategy Board (TSB) PURPOSE (TP11/MFE/6/1/AA129F; EP-SRC TS/G000271/1) and CONVERTED (JeS no. TS/1003053/1), PRISM (EP/N508974/1) and FAB3D programs; TSB CONVERT program