Dual light-emitting Yb3+,Er3+-doped La(IO3)3 iodate nanocrystals: up-conversion and second harmonic generation

The authors report the microwave-assisted hydrothermal synthesis of alpha-La(IO3)(3) nanocrystals doped with Yb3+ and Er3+ ions, along with their structural and optical characterizations. 50-nm-sized alpha-La0.9-xYb0.1Erx(IO3)(3) nanocrystals with x = 0.005, 0.01, and 0.02 were synthesized and dispersed in ethylene glycol. The as-obtained suspensions exhibit both second harmonic generation (SHG) signal and up-conversion photoluminescence (UC-PL) without interplay between the two signals under near-infrared resonant excitation. The relative intensity of SHG and UC-PL emission can be modulated according to the excitation wavelength. The most intense UC-PL signal is obtained from a 980-nm excitation, thanks to the sensitization of Er3+ by Yb3+.