LASER SPECTROSCOPY OF NANOCRYSTALLINE EU2O3 AND EU3+Y2O3

This letter presents optical spectra of EU(3+) in nanocrystalline Eu2O 3 and EU(3+):Y2O3. The nanocrystalline particles condense in the monoc linic crystal structure after CO2-laser vaporization of metal oxide ce ramics. The spectra of 14 nm Eu2O3 particles have the same sharp lines as do micrometer-size particles, and the spectra of 5 nm Eu2O3 partic les show the sharp lines superimposed on broad and shifted bands. The spectra of 12 nm particles prepared from Eu0.2Y1.8O3, starting materia l show two phases that are attributed to slightly disordered Eu2O3 and crystalline Eu3+:Y2O3. The spectra of 5 nm particles prepared from Eu 0.2Y1.8O3 show broad bands similar to the 5 nm Eu2O3 spectra.