Theoretical study on the influence of surface imperfections on the properties of ferroelectric thin films in first-order ferroelectric systems
نویسندگان
چکیده
A generalized Ginzburg–Landau–Devonshire (GLD) theory is used to study the properties of ferroelectric thin films sandwiched between two metal electrodes with a first-order phase transition. By taking into account the effect of the imperfect surface layer and a natural boundary condition, the temperature and film-thickness dependence of the spontaneous polarization and the dielectric susceptibility are calculated. The depolarization field makes the polarization distribution more uniform. In addition, an asymmetric hysteresis loop can be obtained due to the existence of asymmetrical imperfect surface layers.
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