Cluster polarization of Cd2Nb2O7 compound
نویسندگان
چکیده
The direct-current ~dc! electric-field dependence of dielectric constant around paraelectric– ferroelectric transition in Cd2Nb2O7 has been studied. The results show significant suppression of the dielectric constant by the application of dc bias. The electric-field dependence of the dielectric constant at the temperature around paraelectric–ferroelectric phase transition can be well described by the modified Devenshire relation including a cluster term, i.e., «(E)5«12«2E 1«3E 4 1(Px /«0)@cosh(Ex)# . The fit parameters indicate that the polar-cluster carries polarization P5;0.5– 2.5 mC/m with the cluster size of L5;11– 15 nm. © 2000 American Institute of Physics. @S0003-6951~00!04531-9#
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