Green upconverted emission by infrared pump in Ho3+-doped YAlO3

Green (5S2→5I8) upconverted emission in Ho3+-doped YAlO3 under infrared pump (in the spectral range between 730 and 950 nm) is reported. Polarized absorption, emission spectra, and excited state absorption (ESA) spectra were recorded together. Lifetime and power dependency measurements were performed. Possible schemes of upconversion mechanism and their numerical simulation based on a rate equation model are presented. [Copyright &y& Elsevier]