Published online by Cambridge University Press: 24 July 2014
Transparent 0.67(Pb1−xLax)(Mg1/3Nb2/3)O3–0.33(Pb1−xLax)TiO3 (x = 0–0.05) ceramics were successfully prepared without using a hot-pressing technique. The optical transmittance at the wave length of 400–2000 nm increased with increasing lanthanum (La) content, x from 0 to 0.03. The transmittance at 600–2000 nm further increased (with the highest transmittance of 68% at 2000 nm for ceramics with thickness of 0.5 mm) at x = 0.04 and 0.05, while the transmittance at 400–600 nm decreased. X-ray diffraction patterns suggested that the overall increase in the transmittance with x was associated with a change in the crystal systems from a monoclinic phase to a pseudocubic phase, and the decrease at x = 0.04 and 0.05 was related to the formation of an impurity second phase. Their microstructures and dielectric properties were also studied.