Effect of dc bias on the Curie-Weiss exponent in 0.76Pb(Mg_(1/3)Nb_(2/3))O_3-0.24PbTiO_3 ferroelectric single crystal

摘要

Permittivity versus temperature characteristics and Curie-Weiss exponent (CWE) γ in the universal Curie-Weiss law [ε~(-1) = ε_m~(-1)[l+(T-T_c) ~γ/(2δ~2](1 ≤ γ ≤ 2)] as a function of dc bias field were obtained for <001>, <011>, and <111> oriented 0.76Pb(Mg_(1/3)Nb_(2/3))O_3-0.24PbTiO_3 single crystals. Results indicated that γ is a function of dc bias field and three different oriented crystals show slight different γ values but the similar dc field dependence.