Optical properties of highly crystalline Y2O3:Er,Yb nanoparticles prepared by laser ablation in water

Y2O3:Er,Yb nanoparticles were prepared by laser ablation in water. We investigated crystallinity, distribution of dopant, and optical properties of the prepared nanoparticles. The full-width half-maximum (FWHD) of the crystalline peak of nanoparticles measured by an x-ray diffractometer (XRD) barely changed. Further, using scanning transmission electron microscopy-energy dispersive x-ray spectroscopy (STEM-EDX), we confirmed the peaks of Y, Er, Yb, and O. Moreover, on the basis of the optical properties of the nanoparticles, the emission of red (F-2(9/2) -> I-4(15/2)) and green (H-2(11/2), S-4(3/2) -> I-4(15/2)) was confirmed. We also investigated the emission intensity as a function of the excitation power of 980 nm LD in the prepared nanoparticles. The photon avalanche effect was observed at the excitation power of 100 mW. These results confirmed that uniformly Er-Yb-doped Y2O3 nanoparticles were successfully prepared by laser ablation in water.