Field-induced polarization state and phase transition in Pb(Zn1/3Nb2/3)O3:: Dielectric dispersions and nonlinear dielectric constants

The field-induced polarization state and the phase transition to a relaxor in Pb(Zn1/3Nb2/3)O-3 (PZN) were investigated. It was confirmed that the field-induced polarization state in PZN can be realized by applying an electric field at room temperature for a long time. The phase transition from the field-induced polarization state to a relaxor was observed at 114 degrees C during zero-field heating (ZFH) after applying an electric field even at room temperature. The critical slowing down of this transition was observed, where the dielectric dispersion was almost of the single Debye type with beta = 0.95. The second- and third-order nonlinear dielectric constants were measured during ZFH. The sharp peak at 114 degrees C with a negative value in the third-order nonlinear dielectric constant was found. The field-induced polarization state and phase transition in PZN were discussed.