Coercive Field of Ferroelectric TGS and TGSe as a Function of Impressing Rate of Field

Calculations of the ferroelectric coercive field as a function of impressing rate of field have been made on the basis of a two-dimensional model of domain growth; a linear dependence of nucleus density on the applied fields and an anisotropy of sideways velocity of a domain wall motion are taken into account. Experimental results of coercive fields in TGS and TGSe which have been measured by the application of triangular fields are successfully explained by the present treatment. The contribution of newly created nuclei to the polarization reversal cannot be ignored in both crystals.