Dielectric tunability properties of the Pb[(Mg_1/3Nb _2/3)_1-xZr_x]O₃ ceramics

Pb[(Mg_1/3Nb_2/3)_1-xZr _x]O₃ (x = 0.03, 0.06, 0.09, 0.12) ceramics were prepared using a solid state reaction process. The phase structure and surface micrograph were analyzed by X-ray diffraction and scanning electron microscopy. The effects of Zr content on the dielectric and dielectric tunability properties were investigated systematically. The results showed that the high dielectric tunability (>75% at x = 0.12), low dielectric loss (<0.15%) and high temperature stability of these relaxor ferroelectric ceramics were favorable and competitive to those of titanium-containing perovskite structure materials for tunable device applications. The high dielectric non-linear properties were further discussed in terms of the Landau-Ginsberg-Devonshire thermodynamic theory completed with a Langevin term.