Dielectric properties and high tunability of Ba(Ti0.7Zr0.3)O3 ceramics under dc electric field

Abstract

The effect of dc electric field (E) on the dielectric properties of Ba(Ti0.7Zr0.3)O3 ceramics with an obvious ferroelectric-relaxor behavior (Tm∼229 K, 10 kHz) is reported. The dielectric constant is greatly suppressed and a low loss is obtained under dc electric fields (⩽40 kV/cm). The low loss (tan δ∼0.002) and high tunability (∼45%) were obtained for the Ba(Ti0.7Zr0.3)O3 ceramics around 300 K, indicating that it is a promising candidate for tunable materials at room temperature. The field dependence of the temperature (Tm) of the dielectric constant maximum follows the ΔTm∼E2/3 relation, indicating a second-order phase-transition-like behavior.