Highly transparent ceramics with disordered crystal structure

A highly transparent ceramic has been synthesized from Nd³⁺:Y₂O₃ to which 6 mol. % ZrO₂ and 25 mol. % Sc₂O₃ or Lu₂O₃ were added for disordering the crystal structure. Nanopowders with an average particle size of 10–15 nm served as an initial material. They were compacted by the method of uniaxial static pressing combined with ultrasonic action on nanoparticles. The compacting pressure was 200 MPa; the power of the ultrasonic generator was 1.5 kW. It has been shown that the replacement of Y by isovalent Sc and Lu ions and by heterovalent Zr ions reduces the content of pores and the sizes of crystallites. The transparency of the Nd³⁺:Y₂O₃ ceramic with these additives reaches a maximum of 82.2%, and the 40% intensity level spectral band corresponding to the ⁴F_3/2 → ⁴I_11/2 transition widens from 11.4 to 40 nm.