Mechanism of non-linear spaсe-charge polarization in solid dielectrics
Keywords:
proton semiconductors and dielectrics, hydrogen bonded crystals (HBC), proton relaxation and conductivity, non-linear system of equations of Fokker - Planck and Poisson, relaxation modes, polarization frequency harmonicsAbstract
The nonlinear kinetic phenomena during shaping of volume-charge polarization in hydrogen bonded crystals (HBC) is investigated by the methods of quasi – classical kinetic theory. From the solution of the nonlinear system of equations, Fokker – Planck and Poisson, in case of blocking electrodes, it is established that the mathematical description of the relaxation of polarization in HBC, in the region of weak fields (100–1000 kV/m) and high temperatures (T > 350 K) linear approximation of the perturbation theory is sufficient. The coefficients of diffusion and mobility are calculated with respecting of both transitions mechanisms (thermally activated and tunneling) of the protons through potential barrier of parabolic shape. Proton - proton and proton - phonon interaction is not considered. The proposed scheme for solving the kinetic equation can be applied to other, similar to the HBC type and properties of the crystal lattice crystals with ionic conductivity.