Red photoluminescence in NdAlO3 crystalline ceramic powders prepared by combustion synthesis

Red light (two bands peaked at λ ∼680 and ∼697 nm), visible by naked eye, is emitted by crystalline ceramic powders of NdAlO3 prepared by direct combustion synthesis when the sample is irradiated by unfocused ultraviolet pulsed laser light (λ = 337 nm). This is the first observation of luminescence at the visible from NdAlO3 structure. The red emission can be explained by assuming that the quantum cutting process 4D3/2 → 4F9/2 → 4I9/2 is the relevant relaxation mechanism involved in the down-conversion process.