THE EFFECT OF D-PHENYLALANINE ADMIXTURE ON DIELECTRIC-PROPERTIES AND DOMAIN-STRUCTURE OF TGS CRYSTALS

The effect of D-phenylalanine admixture on dielectric properties and d omain structure of TGS crystal was studied. Temperature measurements o f permittivity of the samples were performed for selected frequencies of the measuring field, with and without an external constant electric field. Moreover, temperature measurements of spontaneous polarization and coercive field were carried out for samples of different concentr ation of D-Phe admixture. With increasing concentration of the admixtu re in the solution from which the studied crystals were grown the valu es of maximum permittivity and spontaneous polarization decrease while the coercive field increases. Domain structure of the DPTGS crystals was observed in the process of spontaneous ageing by the liquid crysta l method.