Phase structure and vibrational spectra of rare-earth-oxide ceramics of Dy2(1-x)Tm2xO3

Rare-earth-sesquioxide ceramics have been found to possess potential applications in solid-state lasers due to their excellent physical and chemical properties as well as low cost. In this paper, composite powders with the composition of Dy2(1-x)Tm2xO3 were prepared by ball milling method and corresponding ceramics were obtained using the pressureless sintering technique. Phase structure and vibrational spectra were investigated using X-ray diffraction, Raman spectrometer, and FT-IR spectrometer. It is shown that the mixture of Dy2O3 and Tm2O3 converts to an ordered solid solution of body-centered cubic structure after heat treatment at 1,100 degrees C for 4 h. It is also found that the cell constants of ceramics decrease linearly with the increase of Tm2O3 content. Raman spectra analysis demonstrates that bond length plays a major role in determining the frequencies of Raman bands at high-frequency range and that peak positions exhibit a blue shift with the increase of Tm2O3 content due to decreasing cell constant. Similar phenomenon is also observed in infrared spectra, which shows linearly increasing infrared band frequency with decreasing cell volume. The ball milling method used for preparing composite powders and vibrational spectra analysis in this work provide some important references for the study of laser ceramics containing Dy2O3 and Tm2O3.