On the role of traps in the BaMgAl10O17:Eu2+ fluorescence mechanisms

The role of traps on the BaMgAl10O17:Eu2+ phosphor fluorescence mechanism has been investigated. Comparing the fluorescence intensities obtained as a functions of excitation wavelength and temperature, the importance of traps on the quantum yield is demonstrated. The results show that three different processes can be distinguished in the BaMgAl10O17:Eu2+ phosphor fluorescence depending on the temperature and on the excitation wavelength: a quenching from the 5d level of the europium ions due to the temperature (temperature range between 300 and 700 K), an auto-ionization process of the divalent europium ions (temperature range between 150 and 300 K) and a quenching due to non-radiative recombination of electron-hole pairs created by VUV excitation during the energy migration (300-700 K).