Influence of x‐ray irradiation on doped europium in BaMgAl10O17 studied by x‐ray absorption fine structure and x‐ray diffraction

Abstract— We studied the influence of x‐ray irradiation on the doped europium ion in BaMgAl₁₀O₁₇ (BAM) by x‐ray absorption fine structure measurement and x‐ray diffraction. We found that x‐ray irradiation promoted oxidation of doped europium and fading emissions. However, no difference was found in x‐ray diffraction patterns before and after x‐ray irradiation. We concluded that the fading of BAM after x‐ray irradiation was mainly caused by oxidation of the doped europium in the BAM.     

Effect on deoxidation of doped europium in oxidized BaMgAl10O17

Abstract— We studied the effect of the deoxidation of oxidized blue‐light‐emitting europium‐doped BaMgAl₁₀O₁₇ (BAM) phosphor in a plasma‐display panel by making photoluminescence and powder X‐ray diffraction measurements and by X‐ray absorption fine structure analysis. Photoluminescence spectra, powder X‐ray diffraction, and X‐ray absorption near‐edge structure, and extended X‐ray absorption fine structure spectra of BAM at the europium L₃‐edge suggest that the oxidized BAM annealed in air is revived by heating in a H₂/N₂ (5% H₂) reducing atmosphere above 500°C.     

Orange‐red upconversion luminescence of Sm3+‐doped ZnO‐B2O3‐SiO2 glass by infrared femtosecond laser irradiation

Abstract— Near‐infrared‐to‐visible upconversion luminescence was observed in Sm³⁺‐doped ZnO‐B₂O₃‐SiO₂ glass under femtosecond laser irradiation. The luminescence spectra show that the upconversion luminescence originates from ⁴G^5/2 to ⁶H^j/2 (j = 5, 7, 9) transition of Sm³⁺. The dependence of the fluorescence intensity of Sm³⁺ on the pump power indicates that a two‐photon absorption process is dominant in the conversion of infrared radiation to the visible luminescence. The analysis of the upconversion mechanism reveals that the simultaneous absorption of two infrared photons produces the population of upper excited states, which leads to the characteristic orange‐red emission of Sm³⁺. A three‐dimensional display is demonstrated based on the multiphoton absorption upconversion luminescence.