Laser spectroscopy of nanocrystalline Eu2O3 and Eu3+:Y2O3

This letter presents optical spectra of Eu3+ in nanocrystalline Eu2O3 and Eu3+:Y2O3. The nanocrystalline particles condense in the monoclinic crystal structure after CO2-laser vaporization of metal oxide ceramics. The spectra of 14 nm Eu2O3 particles have the same sharp lines as do micrometer-size particles, and the spectra of 5 nm Eu2O3 particles show the sharp lines superimposed on broad and shifted bands. The spectra of 12 nm particles prepared from Eu0.2Y1.8O3 starting material show two phases that are attributed to slightly disordered Eu2O3 and crystalline Eu3+:Y2O3. The spectra of 5 nm particles prepared from Eu0.2Y1.8O3 show broad bands similar to the 5 nm Eu2O3 spectra.