M ay 2 00 4 Polarization kinetics in ferroelectrics with regard to fluctuations
نویسنده
چکیده
The kinetics of fluctuations and switching of polarization in ferroelectrics, described by the Landau–Ginzburg Hamiltonian, is considered, based on a multi–dimensional Fokker–Planck equation. It describes the time evolution of the probability distribution function over the polarization field configurations in presence of a time–dependent external field. The Fokker–Planck equation in the Fourier representation is obtained, which can be solved numerically, including a finite number of modes. An example calculation is presented, showing the polarization hysteresis in the zero–mode (spatially homogeneous) approximation.
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